diff --git a/include/hack.h b/include/hack.h
index 3e0b9c306..9af8a3fda 100644
--- a/include/hack.h
+++ b/include/hack.h
@@ -12,6 +12,7 @@
 #include "lint.h"
 
 #include "align.h"
+#include "nhconst.h"
 #include "dungeon.h"
 #include "stairs.h"
 #include "objclass.h"
@@ -46,7 +47,6 @@
 #define ON 1
 #define OFF 0
 #define BOLT_LIM 8        /* from this distance ranged attacks will be made */
-#define MAX_CARR_CAP 1000 /* so that boulders can be heavier */
 #define DUMMY { 0 }       /* array initializer, letting [1..N-1] default */
 #define DEF_NOTHING ' '   /* default symbol for NOTHING and UNEXPLORED  */
 
@@ -65,9 +65,6 @@
 #define CXN_ARTICLE 8   /* include a/an/the prefix */
 #define CXN_NOCORPSE 16 /* suppress " corpse" suffix */
 
-/* weight increment of heavy iron ball */
-#define IRON_BALL_W_INCR 160
-
 /* number of turns it takes for vault guard to show up */
 #define VAULT_GUARD_TIME 30
 
diff --git a/include/monsters.h b/include/monsters.h
index 14278e339..408f4a888 100644
--- a/include/monsters.h
+++ b/include/monsters.h
@@ -590,7 +590,7 @@
         LVL(4, 0, 8, 10, 0), (G_GENO | 2),
         A(ATTK(AT_NONE, AD_COLD, 0, 6),
           NO_ATTK, NO_ATTK, NO_ATTK, NO_ATTK, NO_ATTK),
-        SIZ(50, 20, MS_SILENT, MZ_MEDIUM), MR_COLD | MR_POISON,
+        SIZ(WT_JELLY, 20, MS_SILENT, MZ_MEDIUM), MR_COLD | MR_POISON,
         MR_COLD | MR_POISON,
         M1_BREATHLESS | M1_AMORPHOUS | M1_NOEYES | M1_NOLIMBS | M1_NOHEAD
             | M1_MINDLESS | M1_NOTAKE,
@@ -600,7 +600,7 @@
         LVL(5, 0, 8, 10, 0), (G_GENO | 1),
         A(ATTK(AT_NONE, AD_ACID, 0, 6),
           NO_ATTK, NO_ATTK, NO_ATTK, NO_ATTK, NO_ATTK),
-        SIZ(50, 20, MS_SILENT, MZ_MEDIUM),
+        SIZ(WT_JELLY, 20, MS_SILENT, MZ_MEDIUM),
         MR_ACID | MR_STONE, MR_ACID | MR_STONE,
         M1_BREATHLESS | M1_AMORPHOUS | M1_NOEYES | M1_NOLIMBS | M1_NOHEAD
             | M1_MINDLESS | M1_ACID | M1_NOTAKE,
@@ -610,7 +610,7 @@
         LVL(6, 3, 8, 20, 0), (G_GENO | 2),
         A(ATTK(AT_ENGL, AD_ACID, 3, 6), ATTK(AT_NONE, AD_ACID, 3, 6),
           NO_ATTK, NO_ATTK, NO_ATTK, NO_ATTK),
-        SIZ(50, 20, MS_SILENT, MZ_MEDIUM),
+        SIZ(WT_JELLY, 20, MS_SILENT, MZ_MEDIUM),
         MR_ACID | MR_STONE, MR_ACID | MR_STONE,
         M1_BREATHLESS | M1_AMORPHOUS | M1_NOEYES | M1_NOLIMBS | M1_NOHEAD
             | M1_MINDLESS | M1_ACID | M1_NOTAKE,
@@ -701,14 +701,14 @@
         LVL(3, 12, 9, 20, 0), (G_GENO | 2),
         A(ATTK(AT_CLAW, AD_SITM, 0, 0), ATTK(AT_CLAW, AD_SEDU, 0, 0),
           NO_ATTK, NO_ATTK, NO_ATTK, NO_ATTK),
-        SIZ(600, 300, MS_SEDUCE, MZ_HUMAN), 0, 0, M1_HUMANOID | M1_TPORT,
+        SIZ(WT_NYMPH, 300, MS_SEDUCE, MZ_HUMAN), 0, 0, M1_HUMANOID | M1_TPORT,
         M2_HOSTILE | M2_FEMALE | M2_COLLECT, M3_INFRAVISIBLE,
         5, CLR_GREEN, WOOD_NYMPH),
     MON(NAM("water nymph"), S_NYMPH,
         LVL(3, 12, 9, 20, 0), (G_GENO | 2),
         A(ATTK(AT_CLAW, AD_SITM, 0, 0), ATTK(AT_CLAW, AD_SEDU, 0, 0),
           NO_ATTK, NO_ATTK, NO_ATTK, NO_ATTK),
-        SIZ(600, 300, MS_SEDUCE, MZ_HUMAN), 0, 0,
+        SIZ(WT_NYMPH, 300, MS_SEDUCE, MZ_HUMAN), 0, 0,
         M1_HUMANOID | M1_TPORT | M1_SWIM, M2_HOSTILE | M2_FEMALE | M2_COLLECT,
         M3_INFRAVISIBLE,
         5, CLR_BLUE, WATER_NYMPH),
@@ -716,7 +716,7 @@
         LVL(3, 12, 9, 20, 0), (G_GENO | 2),
         A(ATTK(AT_CLAW, AD_SITM, 0, 0), ATTK(AT_CLAW, AD_SEDU, 0, 0),
           NO_ATTK, NO_ATTK, NO_ATTK, NO_ATTK),
-        SIZ(600, 300, MS_SEDUCE, MZ_HUMAN), 0, 0, M1_HUMANOID | M1_TPORT,
+        SIZ(WT_NYMPH, 300, MS_SEDUCE, MZ_HUMAN), 0, 0, M1_HUMANOID | M1_TPORT,
         M2_HOSTILE | M2_FEMALE | M2_COLLECT, M3_INFRAVISIBLE,
         5, CLR_BROWN, MOUNTAIN_NYMPH),
     /*
@@ -1052,7 +1052,7 @@
         LVL(3, 1, 0, 0, 0), (G_GENO | G_NOCORPSE | 2),
         A(ATTK(AT_ENGL, AD_PHYS, 1, 6),
           NO_ATTK, NO_ATTK, NO_ATTK, NO_ATTK, NO_ATTK),
-        SIZ(0, 0, MS_SILENT, MZ_HUGE), MR_SLEEP | MR_POISON | MR_STONE, 0,
+        SIZ(WT_ETHEREAL, 0, MS_SILENT, MZ_HUGE), MR_SLEEP | MR_POISON | MR_STONE, 0,
         M1_FLY | M1_BREATHLESS | M1_NOEYES | M1_NOLIMBS | M1_NOHEAD
             | M1_MINDLESS | M1_AMORPHOUS | M1_UNSOLID,
         M2_HOSTILE | M2_NEUTER, 0,
@@ -1061,7 +1061,7 @@
         LVL(4, 20, 2, 30, 0), (G_GENO | G_NOCORPSE | 2),
         A(ATTK(AT_ENGL, AD_BLND, 2, 8),
           NO_ATTK, NO_ATTK, NO_ATTK, NO_ATTK, NO_ATTK),
-        SIZ(0, 0, MS_SILENT, MZ_HUGE), MR_SLEEP | MR_POISON | MR_STONE, 0,
+        SIZ(WT_ETHEREAL, 0, MS_SILENT, MZ_HUGE), MR_SLEEP | MR_POISON | MR_STONE, 0,
         M1_FLY | M1_BREATHLESS | M1_NOEYES | M1_NOLIMBS | M1_NOHEAD
             | M1_MINDLESS,
         M2_HOSTILE | M2_NEUTER, 0,
@@ -1070,7 +1070,7 @@
         LVL(5, 20, 2, 30, 0), (G_NOHELL | G_GENO | G_NOCORPSE | 1),
         A(ATTK(AT_ENGL, AD_COLD, 1, 6),
           NO_ATTK, NO_ATTK, NO_ATTK, NO_ATTK, NO_ATTK),
-        SIZ(0, 0, MS_SILENT, MZ_HUGE),
+        SIZ(WT_ETHEREAL, 0, MS_SILENT, MZ_HUGE),
         MR_COLD | MR_SLEEP | MR_POISON | MR_STONE, 0,
         M1_FLY | M1_BREATHLESS | M1_NOEYES | M1_NOLIMBS | M1_NOHEAD
             | M1_MINDLESS,
@@ -1080,7 +1080,7 @@
         LVL(6, 20, 2, 30, 0), (G_GENO | G_NOCORPSE | 1),
         A(ATTK(AT_ENGL, AD_ELEC, 1, 6), ATTK(AT_ENGL, AD_DREN, 2, 6),
           ATTK(AT_NONE, AD_ELEC, 0, 4), NO_ATTK, NO_ATTK, NO_ATTK),
-        SIZ(0, 0, MS_SILENT, MZ_HUGE),
+        SIZ(WT_ETHEREAL, 0, MS_SILENT, MZ_HUGE),
         MR_ELEC | MR_SLEEP | MR_DISINT | MR_POISON | MR_STONE, 0,
         M1_FLY | M1_BREATHLESS | M1_NOEYES | M1_NOLIMBS | M1_NOHEAD
             | M1_MINDLESS | M1_UNSOLID,
@@ -1090,7 +1090,7 @@
         LVL(7, 22, 2, 30, 0), (G_HELL | G_GENO | G_NOCORPSE | 2),
         A(ATTK(AT_ENGL, AD_FIRE, 1, 8),
           NO_ATTK, NO_ATTK, NO_ATTK, NO_ATTK, NO_ATTK),
-        SIZ(0, 0, MS_SILENT, MZ_HUGE),
+        SIZ(WT_ETHEREAL, 0, MS_SILENT, MZ_HUGE),
         MR_FIRE | MR_SLEEP | MR_POISON | MR_STONE, 0,
         M1_FLY | M1_BREATHLESS | M1_NOEYES | M1_NOLIMBS | M1_NOHEAD
             | M1_MINDLESS | M1_UNSOLID,
@@ -1100,7 +1100,7 @@
         LVL(8, 22, 2, 30, 0), (G_HELL | G_GENO | G_NOCORPSE | 1),
         A(ATTK(AT_ENGL, AD_FIRE, 1, 10), ATTK(AT_NONE, AD_FIRE, 0, 4),
           NO_ATTK, NO_ATTK, NO_ATTK, NO_ATTK),
-        SIZ(0, 0, MS_SILENT, MZ_HUGE),
+        SIZ(WT_ETHEREAL, 0, MS_SILENT, MZ_HUGE),
         MR_FIRE | MR_SLEEP | MR_POISON | MR_STONE, 0,
         M1_FLY | M1_BREATHLESS | M1_NOEYES | M1_NOLIMBS | M1_NOHEAD
             | M1_MINDLESS | M1_UNSOLID,
@@ -1168,7 +1168,7 @@
         LVL(3, 15, 0, 0, 0), (G_NOCORPSE | G_GENO | 4),
         A(ATTK(AT_EXPL, AD_BLND, 10, 20),
           NO_ATTK, NO_ATTK, NO_ATTK, NO_ATTK, NO_ATTK),
-        SIZ(0, 0, MS_SILENT, MZ_SMALL),
+        SIZ(WT_ETHEREAL, 0, MS_SILENT, MZ_SMALL),
         MR_FIRE | MR_COLD | MR_ELEC | MR_DISINT | MR_SLEEP | MR_POISON
             | MR_ACID | MR_STONE, 0,
         M1_FLY | M1_BREATHLESS | M1_AMORPHOUS | M1_NOEYES | M1_NOLIMBS
@@ -1180,7 +1180,7 @@
         LVL(5, 15, 0, 0, 0), (G_NOCORPSE | G_GENO | 2),
         A(ATTK(AT_EXPL, AD_HALU, 10, 12),
           NO_ATTK, NO_ATTK, NO_ATTK, NO_ATTK, NO_ATTK),
-        SIZ(0, 0, MS_SILENT, MZ_SMALL),
+        SIZ(WT_ETHEREAL, 0, MS_SILENT, MZ_SMALL),
         MR_FIRE | MR_COLD | MR_ELEC | MR_DISINT | MR_SLEEP | MR_POISON
             | MR_ACID | MR_STONE, 0,
         M1_FLY | M1_BREATHLESS | M1_AMORPHOUS | M1_NOEYES | M1_NOLIMBS
@@ -1340,7 +1340,7 @@
         LVL(12, 9, 2, 10, 0), G_GENO,
         A(ATTK(AT_BITE, AD_PHYS, 2, 6),
           NO_ATTK, NO_ATTK, NO_ATTK, NO_ATTK, NO_ATTK),
-        SIZ(1500, 500, MS_ROAR, MZ_HUGE), 0, 0,
+        SIZ(WT_BABY_DRAGON, 500, MS_ROAR, MZ_HUGE), 0, 0,
         M1_FLY | M1_THICK_HIDE | M1_NOHANDS | M1_CARNIVORE,
         M2_HOSTILE | M2_STRONG | M2_GREEDY | M2_JEWELS, 0,
         13, CLR_GRAY, BABY_GRAY_DRAGON),
@@ -1348,7 +1348,7 @@
         LVL(12, 9, 2, 10, 0), G_GENO,
         A(ATTK(AT_BITE, AD_PHYS, 2, 6),
           NO_ATTK, NO_ATTK, NO_ATTK, NO_ATTK, NO_ATTK),
-        SIZ(1500, 500, MS_ROAR, MZ_HUGE), 0, 0,
+        SIZ(WT_BABY_DRAGON, 500, MS_ROAR, MZ_HUGE), 0, 0,
         M1_FLY | M1_THICK_HIDE | M1_NOHANDS | M1_CARNIVORE,
         M2_HOSTILE | M2_STRONG | M2_GREEDY | M2_JEWELS, M3_INFRAVISIBLE,
         13, HI_GOLD, BABY_GOLD_DRAGON),
@@ -1356,7 +1356,7 @@
         LVL(12, 9, 2, 10, 0), G_GENO,
         A(ATTK(AT_BITE, AD_PHYS, 2, 6),
           NO_ATTK, NO_ATTK, NO_ATTK, NO_ATTK, NO_ATTK),
-        SIZ(1500, 500, MS_ROAR, MZ_HUGE), 0, 0,
+        SIZ(WT_BABY_DRAGON, 500, MS_ROAR, MZ_HUGE), 0, 0,
         M1_FLY | M1_THICK_HIDE | M1_NOHANDS | M1_CARNIVORE,
         M2_HOSTILE | M2_STRONG | M2_GREEDY | M2_JEWELS, 0,
         13, DRAGON_SILVER, BABY_SILVER_DRAGON),
@@ -1366,7 +1366,7 @@
         LVL(12, 9, 2, 10, 0), G_GENO,
         A(ATTK(AT_BITE, AD_PHYS, 2, 6),
           NO_ATTK, NO_ATTK, NO_ATTK, NO_ATTK, NO_ATTK),
-        SIZ(1500, 500, MS_ROAR, MZ_HUGE), 0, 0,
+        SIZ(WT_BABY_DRAGON, 500, MS_ROAR, MZ_HUGE), 0, 0,
         M1_FLY | M1_THICK_HIDE | M1_NOHANDS | M1_CARNIVORE,
         M2_HOSTILE | M2_STRONG | M2_GREEDY | M2_JEWELS, 0,
         13, CLR_CYAN, BABY_SHIMMERING_DRAGON),
@@ -1375,7 +1375,7 @@
         LVL(12, 9, 2, 10, 0), G_GENO,
         A(ATTK(AT_BITE, AD_PHYS, 2, 6),
           NO_ATTK, NO_ATTK, NO_ATTK, NO_ATTK, NO_ATTK),
-        SIZ(1500, 500, MS_ROAR, MZ_HUGE), MR_FIRE, 0,
+        SIZ(WT_BABY_DRAGON, 500, MS_ROAR, MZ_HUGE), MR_FIRE, 0,
         M1_FLY | M1_THICK_HIDE | M1_NOHANDS | M1_CARNIVORE,
         M2_HOSTILE | M2_STRONG | M2_GREEDY | M2_JEWELS, M3_INFRAVISIBLE,
         13, CLR_RED, BABY_RED_DRAGON),
@@ -1383,7 +1383,7 @@
         LVL(12, 9, 2, 10, 0), G_GENO,
         A(ATTK(AT_BITE, AD_PHYS, 2, 6),
           NO_ATTK, NO_ATTK, NO_ATTK, NO_ATTK, NO_ATTK),
-        SIZ(1500, 500, MS_ROAR, MZ_HUGE), MR_COLD, 0,
+        SIZ(WT_BABY_DRAGON, 500, MS_ROAR, MZ_HUGE), MR_COLD, 0,
         M1_FLY | M1_THICK_HIDE | M1_NOHANDS | M1_CARNIVORE,
         M2_HOSTILE | M2_STRONG | M2_GREEDY | M2_JEWELS, 0,
         13, CLR_WHITE, BABY_WHITE_DRAGON),
@@ -1391,7 +1391,7 @@
         LVL(12, 9, 2, 10, 0), G_GENO,
         A(ATTK(AT_BITE, AD_PHYS, 2, 6),
           NO_ATTK, NO_ATTK, NO_ATTK, NO_ATTK, NO_ATTK),
-        SIZ(1500, 500, MS_ROAR, MZ_HUGE), MR_SLEEP, 0,
+        SIZ(WT_BABY_DRAGON, 500, MS_ROAR, MZ_HUGE), MR_SLEEP, 0,
         M1_FLY | M1_THICK_HIDE | M1_NOHANDS | M1_CARNIVORE,
         M2_HOSTILE | M2_STRONG | M2_GREEDY | M2_JEWELS, 0,
         13, CLR_ORANGE, BABY_ORANGE_DRAGON),
@@ -1399,7 +1399,7 @@
         LVL(12, 9, 2, 10, 0), G_GENO,
         A(ATTK(AT_BITE, AD_PHYS, 2, 6),
           NO_ATTK, NO_ATTK, NO_ATTK, NO_ATTK, NO_ATTK),
-        SIZ(1500, 500, MS_ROAR, MZ_HUGE), MR_DISINT, 0,
+        SIZ(WT_BABY_DRAGON, 500, MS_ROAR, MZ_HUGE), MR_DISINT, 0,
         M1_FLY | M1_THICK_HIDE | M1_NOHANDS | M1_CARNIVORE,
         M2_HOSTILE | M2_STRONG | M2_GREEDY | M2_JEWELS, 0,
         13, CLR_BLACK, BABY_BLACK_DRAGON),
@@ -1407,7 +1407,7 @@
         LVL(12, 9, 2, 10, 0), G_GENO,
         A(ATTK(AT_BITE, AD_PHYS, 2, 6),
           NO_ATTK, NO_ATTK, NO_ATTK, NO_ATTK, NO_ATTK),
-        SIZ(1500, 500, MS_ROAR, MZ_HUGE), MR_ELEC, 0,
+        SIZ(WT_BABY_DRAGON, 500, MS_ROAR, MZ_HUGE), MR_ELEC, 0,
         M1_FLY | M1_THICK_HIDE | M1_NOHANDS | M1_CARNIVORE,
         M2_HOSTILE | M2_STRONG | M2_GREEDY | M2_JEWELS, 0,
         13, CLR_BLUE, BABY_BLUE_DRAGON),
@@ -1415,7 +1415,7 @@
         LVL(12, 9, 2, 10, 0), G_GENO,
         A(ATTK(AT_BITE, AD_PHYS, 2, 6),
           NO_ATTK, NO_ATTK, NO_ATTK, NO_ATTK, NO_ATTK),
-        SIZ(1500, 500, MS_ROAR, MZ_HUGE), MR_POISON, 0,
+        SIZ(WT_BABY_DRAGON, 500, MS_ROAR, MZ_HUGE), MR_POISON, 0,
         M1_FLY | M1_THICK_HIDE | M1_NOHANDS | M1_CARNIVORE | M1_POIS,
         M2_HOSTILE | M2_STRONG | M2_GREEDY | M2_JEWELS, 0,
         13, CLR_GREEN, BABY_GREEN_DRAGON),
@@ -1423,7 +1423,7 @@
         LVL(12, 9, 2, 10, 0), G_GENO,
         A(ATTK(AT_BITE, AD_PHYS, 2, 6),
           NO_ATTK, NO_ATTK, NO_ATTK, NO_ATTK, NO_ATTK),
-        SIZ(1500, 500, MS_ROAR, MZ_HUGE), MR_ACID | MR_STONE, 0,
+        SIZ(WT_BABY_DRAGON, 500, MS_ROAR, MZ_HUGE), MR_ACID | MR_STONE, 0,
         M1_FLY | M1_THICK_HIDE | M1_NOHANDS | M1_CARNIVORE | M1_ACID,
         M2_HOSTILE | M2_STRONG | M2_GREEDY | M2_JEWELS, 0,
         13, CLR_YELLOW, BABY_YELLOW_DRAGON),
diff --git a/include/nhconst.h b/include/nhconst.h
new file mode 100644
index 000000000..2e074f3f9
--- /dev/null
+++ b/include/nhconst.h
@@ -0,0 +1,42 @@
+/* NetHack 3.7	nhconst.h	$NHDT-Date: 1725653014 2024/09/06 20:03:34 $  $NHDT-Branch: NetHack-3.7 $:$NHDT-Revision: 1.26 $ */
+/* Copyright (c) Michael Allison, 2025. */
+/* NetHack may be freely redistributed.  See license for details. */
+
+#ifndef NHCONST_H
+#define NHCONST_H
+
+/* weight-related constants and thresholds */
+enum weight_constants {
+    WT_ETHEREAL          =    0,
+    WT_SPLASH_THRESHOLD  =    9,  /* weight needed to make splash in water */
+    WT_WEIGHTCAP_STRCON  =   25,  /* str + con multiplied by this for conv to
+                                   * carrying capacity in weight_cap() */
+    WT_WEIGHTCAP_SPARE   =   50,  /* used in weight_cap calc */
+    WT_JELLY             =   50,  /* weight of jelly body */
+    WT_WOUNDEDLEG_REDUCT =  100,  /* wounded legs reduce carrcap by this */
+    WT_TO_DMG            =  100,  /* divisor to convert weight to dmg amt */
+    WT_IRON_BALL_INCR    =  160,  /* weight increment of heavy iron ball */
+    WT_IRON_BALL_BASE    =  480,  /* base starting weight of iron ball */
+    WT_NOISY_INV         =  500,  /* inv_weight() max for noisy fumbling */
+    WT_NYMPH             =  600,  /* weight of nymph body */
+    WT_TOOMUCH_DIAGONAL  =  600,  /* weight_cap threshold for diag squeeze */
+    WT_ELF               =  800,  /* weight of elf body */
+    WT_SQUEEZABLE_INV    =  850,  /* inv_weight() maximum for squeezing */
+    MAX_CARR_CAP         = 1000,  /* max carrying capacity, so that
+                                   * boulders can be heavier */
+    WT_HUMAN             = 1450,  /* weight of human body */
+    WT_BABY_DRAGON       = 1500,  /* weight ob baby dragon body */
+    WT_DRAGON            = 4500,  /* weight of dragon body */
+};
+
+enum monster_speeds {
+    VERY_SLOW    =  3,
+    SLOW_SPEED   =  9,
+    NORMAL_SPEED = 12, /* movement rates */
+    FAST_SPEED   = 15,
+    VERY_FAST    = 24,
+};
+
+#endif /* NHCONST_H */
+
+
diff --git a/include/permonst.h b/include/permonst.h
index 9f11bb1fc..a03e36b4b 100644
--- a/include/permonst.h
+++ b/include/permonst.h
@@ -47,12 +47,6 @@ struct attack {
 
 #define NATTK 6
 
-/*     Weight of human body, elf, dragon
- */
-#define WT_HUMAN 1450U
-#define WT_ELF 800U
-#define WT_DRAGON 4500U
-
 #ifndef ALIGN_H
 #include "align.h"
 #endif
@@ -86,10 +80,4 @@ struct permonst {
 extern NEARDATA struct permonst mons[NUMMONS + 1]; /* the master list of
                                                     * monster types */
 
-#define VERY_SLOW 3
-#define SLOW_SPEED 9
-#define NORMAL_SPEED 12 /* movement rates */
-#define FAST_SPEED 15
-#define VERY_FAST 24
-
 #endif /* PERMONST_H */
diff --git a/src/do.c b/src/do.c
index 41828b8ac..2d1d7d57b 100644
--- a/src/do.c
+++ b/src/do.c
@@ -275,7 +275,7 @@ flooreffects(
          * noise.  Stuff dropped near fountains always misses */
         if ((Blind || (Levitation || Flying)) && !Deaf && u_at(x, y)) {
             if (!Underwater) {
-                if (weight(obj) > 9) {
+                if (weight(obj) > WT_SPLASH_THRESHOLD) {
                     pline("Splash!");
                 } else if (Levitation || Flying) {
                     pline("Plop!");
diff --git a/src/dothrow.c b/src/dothrow.c
index dac67ba82..fbc507c3c 100644
--- a/src/dothrow.c
+++ b/src/dothrow.c
@@ -823,7 +823,7 @@ hurtle_step(genericptr_t arg, coordxy x, coordxy y)
                    && bad_rock(gy.youmonst.data, u.ux, y)
                    && bad_rock(gy.youmonst.data, x, u.uy)) {
             boolean too_much = (gi.invent
-                                && (inv_weight() + weight_cap() > 600));
+                       && (inv_weight() + weight_cap() > WT_TOOMUCH_DIAGONAL));
 
             if (bigmonst(gy.youmonst.data) || too_much) {
                 why = "wedging into a narrow crevice";
@@ -1347,7 +1347,7 @@ toss_up(struct obj *obj, boolean hitsroof)
                                    &dmg, rn1(18, 2));
 
         if (!dmg) { /* probably wasn't a weapon; base damage on weight */
-            dmg = ((int) obj->owt + 99) / 100;
+            dmg = ((int) obj->owt + (WT_TO_DMG - 1)) / WT_TO_DMG;
             dmg = (dmg <= 1) ? 1 : rnd(dmg);
             if (dmg > 6)
                 dmg = 6;
@@ -1770,7 +1770,8 @@ throwit(struct obj *obj,
                 || (is_lava(gb.bhitpos.x, gb.bhitpos.y)
                     && !is_flammable(obj))) {
                 Soundeffect(se_splash, 50);
-                pline((weight(obj) > 9) ? "Splash!" : "Plop!");
+                pline((weight(obj) > WT_SPLASH_THRESHOLD)
+                      ? "Splash!" : "Plop!");
             }
         }
         if (flooreffects(obj, gb.bhitpos.x, gb.bhitpos.y, "fall")) {
diff --git a/src/hack.c b/src/hack.c
index 6bd838e16..908f9e5e9 100644
--- a/src/hack.c
+++ b/src/hack.c
@@ -135,7 +135,8 @@ revive_nasty(coordxy x, coordxy y, const char *msg)
     return revived;
 }
 
-#define squeezeablylightinvent() (!gi.invent || inv_weight() <= -850)
+#define squeezeablylightinvent() (!gi.invent \
+    || inv_weight() <= (WT_SQUEEZABLE_INV * -1))
 
 /* can hero move onto a spot containing one or more boulders?
    used for m<dir> and travel and during boulder push failure */
@@ -4195,7 +4196,8 @@ weight_cap(void)
        functions enough in that situation to enhance carrying capacity */
     BLevitation &= ~I_SPECIAL;
 
-    carrcap = 25 * (ACURRSTR + ACURR(A_CON)) + 50;
+    carrcap = (WT_WEIGHTCAP_STRCON * (ACURRSTR + ACURR(A_CON)))
+               + WT_WEIGHTCAP_SPARE;
     if (Upolyd) {
         /* consistent with can_carry() in mon.c */
         if (gy.youmonst.data->mlet == S_NYMPH)
@@ -4216,9 +4218,9 @@ weight_cap(void)
             carrcap = MAX_CARR_CAP;
         if (!Flying) {
             if (EWounded_legs & LEFT_SIDE)
-                carrcap -= 100;
+                carrcap -= WT_WOUNDEDLEG_REDUCT;
             if (EWounded_legs & RIGHT_SIDE)
-                carrcap -= 100;
+                carrcap -= WT_WOUNDEDLEG_REDUCT;
         }
     }
 
diff --git a/src/monst.c b/src/monst.c
index 4b7f57fb1..30eec13b5 100644
--- a/src/monst.c
+++ b/src/monst.c
@@ -4,6 +4,7 @@
 /* NetHack may be freely redistributed.  See license for details. */
 
 #include "config.h"
+#include "nhconst.h"
 #include "permonst.h"
 #include "wintype.h"
 #include "sym.h"
diff --git a/src/mthrowu.c b/src/mthrowu.c
index a0d462efd..13a76175d 100644
--- a/src/mthrowu.c
+++ b/src/mthrowu.c
@@ -1439,10 +1439,10 @@ hit_bars(
         if (your_fault && (otmp->otyp == WAR_HAMMER
                            || otmp->otyp == HEAVY_IRON_BALL)) {
             /* iron ball isn't a weapon or wep-tool so doesn't use obj->spe;
-               weight is normally 480 but can be increased by increments
-               of 160 (scrolls of punishment read while already punished) */
+               weight is normally 48000 but can be increased by increments
+               of 16000 (scrolls of punishment read while already punished) */
             int spe = ((otmp->otyp == HEAVY_IRON_BALL) /* 3+ for iron ball */
-                       ? ((int) otmp->owt / IRON_BALL_W_INCR)
+                       ? ((int) otmp->owt / WT_IRON_BALL_INCR)
                        : otmp->spe);
             /* chance: used in saving throw for the bars; more likely to
                break those when 'chance' is _lower_; acurrstr(): 3..25 */
diff --git a/src/objects.c b/src/objects.c
index 45ceaeeab..f9646a54d 100644
--- a/src/objects.c
+++ b/src/objects.c
@@ -3,6 +3,7 @@
 /* NetHack may be freely redistributed.  See license for details. */
 
 #include "config.h"
+#include "nhconst.h"
 #include "obj.h"
 
 #include "prop.h"
diff --git a/src/objnam.c b/src/objnam.c
index b4e4ae8dd..d3ce48ffb 100644
--- a/src/objnam.c
+++ b/src/objnam.c
@@ -5357,7 +5357,7 @@ readobjnam(char *bp, struct obj *no_wish)
     }
     d.otmp->owt = weight(d.otmp);
     if (d.very && d.otmp->otyp == HEAVY_IRON_BALL)
-        d.otmp->owt += IRON_BALL_W_INCR;
+        d.otmp->owt += WT_IRON_BALL_INCR;
 
     return d.otmp;
 }
diff --git a/src/read.c b/src/read.c
index f4cc95ac6..9f0383de7 100644
--- a/src/read.c
+++ b/src/read.c
@@ -2938,7 +2938,7 @@ punish(struct obj *sobj)
         You("are being punished for your misbehavior!");
     if (Punished) {
         Your("iron ball gets heavier.");
-        uball->owt += IRON_BALL_W_INCR * (1 + cursed_levy);
+        uball->owt += WT_IRON_BALL_INCR * (1 + cursed_levy);
         return;
     }
     if (amorphous(gy.youmonst.data) || is_whirly(gy.youmonst.data)
diff --git a/src/timeout.c b/src/timeout.c
index 58c575fd1..81f62d531 100644
--- a/src/timeout.c
+++ b/src/timeout.c
@@ -910,7 +910,7 @@ nh_timeout(void)
                      * are to make noise when you fumble.  Adjustments
                      * to this number must be thoroughly play tested.
                      */
-                    if ((inv_weight() > -500)) {
+                    if ((inv_weight() > (WT_NOISY_INV * -1))) {
                         if (!Deaf)
                             You("make a lot of noise!");
                         wake_nearby(FALSE);
diff --git a/src/trap.c b/src/trap.c
index b26c471a8..21adb2314 100644
--- a/src/trap.c
+++ b/src/trap.c
@@ -5366,7 +5366,7 @@ try_disarm(
     /* duplicate tight-space checks from test_move */
     if (u.dx && u.dy && bad_rock(gy.youmonst.data, u.ux, ttmp->ty)
         && bad_rock(gy.youmonst.data, ttmp->tx, u.uy)) {
-        if ((gi.invent && (inv_weight() + weight_cap() > 600))
+        if ((gi.invent && (inv_weight() + weight_cap() > WT_TOOMUCH_DIAGONAL))
             || bigmonst(gy.youmonst.data)) {
             /* don't allow untrap if they can't get thru to it */
             You("are unable to reach the %s!", trapname(ttype, FALSE));
diff --git a/src/weapon.c b/src/weapon.c
index 12e5b5d99..c2da65a58 100644
--- a/src/weapon.c
+++ b/src/weapon.c
@@ -310,7 +310,7 @@ dmgval(struct obj *otmp, struct monst *mon)
         int wt = (int) objects[HEAVY_IRON_BALL].oc_weight;
 
         if ((int) otmp->owt > wt) {
-            wt = ((int) otmp->owt - wt) / IRON_BALL_W_INCR;
+            wt = ((int) otmp->owt - wt) / WT_IRON_BALL_INCR;
             tmp += rnd(4 * wt);
             if (tmp > 25)
                 tmp = 25; /* objects[].oc_wldam */
diff --git a/sys/msdos/Makefile.GCC b/sys/msdos/Makefile.GCC
index 9ed3b27a2..727e56534 100644
--- a/sys/msdos/Makefile.GCC
+++ b/sys/msdos/Makefile.GCC
@@ -415,11 +415,11 @@ DECL_H	   = $(YOU_H)		$(INCL)/spell.h	    $(INCL)/color.h    \
 GLOBAL_H   = $(PCCONF_H)	$(INCL)/coord.h	   $(INCL)/global.h
 HACK_H	   = $(CONFIG_H)	$(INCL)/context.h  $(DUNGEON_H)	       \
 	     $(DECL_H)	      	$(DISPLAY_H)	   $(INCL)/sym.h       \
-	     $(INCL)/defsym.h   $(INCL)/mkroom.h   $(INCL)/objclass.h  \
-	     $(INCL)/trap.h     $(INCL)/flag.h     $(RM_H)             \
-	     $(INCL)/vision.h   $(INCL)/wintype.h  $(INCL)/engrave.h   \
-	     $(INCL)/rect.h     $(INCL)/hack.h     $(REGION_H)         \
-	     $(INCL)/sys.h
+	     $(INCL)/defsym.h   $(INCL)/mkroom.h   $(INCL)/nhconst.h   \
+	     $(INCL)/objclass.h $(INCL)/trap.h     $(INCL)/flag.h      \
+	     $(RM_H)            $(INCL)/vision.h   $(INCL)/wintype.h   \
+	     $(INCL)/engrave.h  $(INCL)/rect.h     $(INCL)/hack.h      \
+	     $(REGION_H)        $(INCL)/sys.h
 DLB_H      = $(INCL)/dlb.h
 
 ifeq ($(SUPPRESS_GRAPHICS),Y)
diff --git a/sys/unix/Makefile.src b/sys/unix/Makefile.src
index 7532dc098..92f89912e 100644
--- a/sys/unix/Makefile.src
+++ b/sys/unix/Makefile.src
@@ -564,11 +564,11 @@ HACKINCL = align.h artifact.h artilist.h attrib.h botl.h \
 	display.h dlb.h dungeon.h engrave.h extern.h flag.h fnamesiz.h \
 	func_tab.h global.h warnings.h hack.h lint.h mextra.h mfndpos.h \
 	micro.h mkroom.h monattk.h mondata.h monflag.h monst.h monsters.h \
-	nhmd4.h obj.h objects.h objclass.h optlist.h patchlevel.h pcconf.h \
-	permonst.h prop.h rect.h region.h selvar.h sym.h defsym.h rm.h sp_lev.h \
-	spell.h sndprocs.h seffects.h stairs.h sys.h tcap.h timeout.h \
-	tradstdc.h trap.h unixconf.h vision.h vmsconf.h wintty.h wincurs.h \
-	winX.h winprocs.h wintype.h you.h youprop.h cstd.h
+	nhconst.h nhmd4.h obj.h objects.h objclass.h optlist.h patchlevel.h \
+	pcconf.h permonst.h prop.h rect.h region.h selvar.h sym.h defsym.h \
+	rm.h sp_lev.h spell.h sndprocs.h seffects.h stairs.h sys.h tcap.h \
+	timeout.h tradstdc.h trap.h unixconf.h vision.h vmsconf.h wintty.h \
+	wincurs.h winX.h winprocs.h wintype.h you.h youprop.h cstd.h
 
 HSOURCES = $(HACKINCL) dgn_file.h
 
@@ -883,15 +883,15 @@ $(HACK_H): $(CONFIG_H) ../include/align.h ../include/artilist.h \
 		../include/hack.h ../include/lint.h ../include/mextra.h \
 		../include/mkroom.h ../include/monattk.h ../include/mondata.h \
 		../include/monflag.h ../include/monst.h ../include/monsters.h \
-		../include/nhlua.h ../include/obj.h ../include/objclass.h \
-		../include/objects.h ../include/permonst.h ../include/prop.h \
-		../include/quest.h ../include/rect.h ../include/region.h \
-		../include/rm.h ../include/seffects.h ../include/selvar.h \
-		../include/skills.h ../include/sndprocs.h ../include/spell.h \
-		../include/stairs.h ../include/sym.h ../include/sys.h \
-		../include/timeout.h ../include/trap.h ../include/vision.h \
-		../include/winprocs.h ../include/wintype.h ../include/you.h \
-		../include/youprop.h
+		../include/nhconst.h ../include/nhlua.h ../include/obj.h \
+		../include/objclass.h ../include/objects.h ../include/permonst.h \
+		../include/prop.h ../include/quest.h ../include/rect.h \
+		../include/region.h ../include/rm.h ../include/seffects.h \
+		../include/selvar.h ../include/skills.h ../include/sndprocs.h \
+		../include/spell.h ../include/stairs.h ../include/sym.h \
+		../include/sys.h ../include/timeout.h ../include/trap.h \
+		../include/vision.h ../include/winprocs.h ../include/wintype.h \
+		../include/you.h ../include/youprop.h
 	touch $(HACK_H)
 #
 $(TARGETPFX)cppregex.o: ../sys/share/cppregex.cpp $(CONFIG_H)
diff --git a/sys/vms/Makefile.src b/sys/vms/Makefile.src
index df797c38c..6635a5690 100644
--- a/sys/vms/Makefile.src
+++ b/sys/vms/Makefile.src
@@ -393,7 +393,7 @@ $(HACK_H) : $(INC)hack.h $(CONFIG_H) $(INC)align.h \
 		$(INC)dungeon.h $(INC)sym.h $(INC)defsym.h $(INC)mkroom.h \
 		$(INC)objclass.h $(INC)youprop.h $(INC)prop.h \
 		$(INC)permonst.h $(INC)monattk.h \
-		$(INC)monflag.h $(INC)mondata.h $(INC)pm.h \
+		$(INC)monflag.h $(INC)mondata.h $(INC)nhconst.h $(INC)pm.h \
 		$(INC)wintype.h $(INC)context.h $(INC)decl.h $(INC)quest.h \
 		$(INC)spell.h $(INC)color.h $(INC)obj.h \
 		$(INC)you.h $(INC)attrib.h $(INC)monst.h \
diff --git a/sys/windows/Makefile.nmake b/sys/windows/Makefile.nmake
index 40fe46230..b25fbb208 100644
--- a/sys/windows/Makefile.nmake
+++ b/sys/windows/Makefile.nmake
@@ -1121,15 +1121,15 @@ HACK_H = $(CONFIG_H) $(INCL)align.h $(INCL)artilist.h \
 	$(INCL)hack.h $(INCL)lint.h $(INCL)mextra.h \
 	$(INCL)mkroom.h $(INCL)monattk.h $(INCL)mondata.h \
 	$(INCL)monflag.h $(INCL)monst.h $(INCL)monsters.h \
-	$(INCL)nhlua.h $(INCL)obj.h $(INCL)objclass.h \
-	$(INCL)objects.h $(INCL)permonst.h $(INCL)prop.h \
-	$(INCL)quest.h $(INCL)rect.h $(INCL)region.h \
-	$(INCL)rm.h $(INCL)seffects.h $(INCL)selvar.h \
-	$(INCL)skills.h $(INCL)sndprocs.h $(INCL)spell.h \
-	$(INCL)stairs.h $(INCL)sym.h $(INCL)sys.h \
-	$(INCL)timeout.h $(INCL)trap.h $(INCL)vision.h \
-	$(INCL)winprocs.h $(INCL)wintype.h $(INCL)you.h \
-	$(INCL)youprop.h
+	$(INCL)nhconst.h $(INCL)nhlua.h $(INCL)obj.h \
+	$(INCL)objclass.h $(INCL)objects.h $(INCL)permonst.h \
+	$(INCL)prop.h $(INCL)quest.h $(INCL)rect.h \
+	$(INCL)region.h $(INCL)rm.h $(INCL)seffects.h \
+	$(INCL)selvar.h $(INCL)skills.h $(INCL)sndprocs.h \
+	$(INCL)spell.h $(INCL)stairs.h $(INCL)sym.h \
+	$(INCL)sys.h $(INCL)timeout.h $(INCL)trap.h \
+	$(INCL)vision.h $(INCL)winprocs.h $(INCL)wintype.h \
+	$(INCL)you.h $(INCL)youprop.h
 
 TILE_H      = $(WSHR)tile.h