diff --git a/src/battle.c b/src/battle.c
index b7e4b92a3..6ab969c93 100644
--- a/src/battle.c
+++ b/src/battle.c
@@ -1138,7 +1138,7 @@ static void demon_dazzle(fighter *af, troop dt) {
     if (u_race(af->unit) == get_race(RC_DAEMON)) {
         if (!(df->person[dt.index].flags & (FL_COURAGE | FL_DAZZLED))) {
             df->person[dt.index].flags |= FL_DAZZLED;
-            df->person[dt.index].defence--;
+            df->person[dt.index].defense--;
         }
     }
 }
@@ -1191,7 +1191,7 @@ static void destroy_items(troop dt) {
 
 }
 
-static void calculate_defence_type(troop dt, troop at, int type, bool missile,
+static void calculate_defense_type(troop dt, troop at, int type, bool missile,
     const weapon_type **dwtype, int *defskill) {
   const weapon *weapon;
   weapon = select_weapon(dt, false, true);      /* missile=true to get the unmodified best weapon she has */
@@ -1320,7 +1320,7 @@ terminate(troop dt, troop at, int type, const char *damage_formula, bool missile
     ++at.fighter->hits;
 
     calculate_attack_type(at, dt, type, missile, &awtype, &attskill, &magic);
-    calculate_defence_type(at, dt, type, missile, &awtype, &attskill);
+    calculate_defense_type(at, dt, type, missile, &awtype, &attskill);
 
     if (is_riding(at) && (awtype == NULL || (fval(awtype, WTF_HORSEBONUS)
         && !fval(awtype, WTF_MISSILE)))) {
@@ -1946,7 +1946,7 @@ int skilldiff(troop at, troop dt, int dist)
         rc_goblin = get_race(RC_GOBLIN);
     }
     skdiff += af->person[at.index].attack;
-    skdiff -= df->person[dt.index].defence;
+    skdiff -= df->person[dt.index].defense;
 
     if (df->person[dt.index].flags & FL_SLEEPING)
         skdiff += 2;
@@ -2075,7 +2075,7 @@ void dazzle(battle * b, troop * td)
     }
 
     td->fighter->person[td->index].flags |= FL_DAZZLED;
-    td->fighter->person[td->index].defence--;
+    td->fighter->person[td->index].defense--;
 }
 
 void damage_building(battle * b, building * bldg, int damage_abs)
@@ -2241,7 +2241,7 @@ static void attack(battle * b, troop ta, const att * a, int numattack)
                     td.fighter->person[td.index].attack -= 1;
                 }
                 else {
-                    td.fighter->person[td.index].defence -= 1;
+                    td.fighter->person[td.index].defense -= 1;
                 }
                 c--;
             }
@@ -3184,7 +3184,7 @@ fighter *make_fighter(battle * b, unit * u, side * s1, bool attack)
     strongmen = trollbelts(u);
     if (strongmen > fig->unit->number) strongmen = fig->unit->number;
 
-    /* Hitpoints, Attack- und Defence-Boni f�r alle Personen */
+    /* Hitpoints, Attack- und Defense-Boni fuer alle Personen */
     for (i = 0; i < fig->alive; i++) {
         assert(i < fig->unit->number);
         fig->person[i].hp = h;
diff --git a/src/battle.h b/src/battle.h
index bad2dd508..eb6335bce 100644
--- a/src/battle.h
+++ b/src/battle.h
@@ -173,7 +173,7 @@ extern "C" {
         struct person {
             int hp;                   /* Trefferpunkte der Personen */
             int attack;
-            int defence;
+            int defense;
             int damage;
             int flags;
             int speed;
diff --git a/src/battle.test.c b/src/battle.test.c
index 20b167c1f..53c47f0e5 100644
--- a/src/battle.test.c
+++ b/src/battle.test.c
@@ -303,7 +303,7 @@ static void test_building_bonus_respects_size(CuTest * tc)
     test_teardown();
 }
 
-static void test_building_defence_bonus(CuTest * tc)
+static void test_building_defense_bonus(CuTest * tc)
 {
     building_type * btype;
 
@@ -570,7 +570,7 @@ static void test_battle_skilldiff(CuTest *tc)
     CuAssertIntEquals(tc, 0, skilldiff(ta, td, 0));
 
     ta.fighter->person[0].attack = 2;
-    td.fighter->person[0].defence = 1;
+    td.fighter->person[0].defense = 1;
     CuAssertIntEquals(tc, 1, skilldiff(ta, td, 0));
 
     td.fighter->person[0].flags |= FL_SLEEPING;
@@ -888,7 +888,7 @@ CuSuite *get_battle_suite(void)
     SUITE_ADD_TEST(suite, test_defenders_get_building_bonus);
     SUITE_ADD_TEST(suite, test_attackers_get_no_building_bonus);
     SUITE_ADD_TEST(suite, test_building_bonus_respects_size);
-    SUITE_ADD_TEST(suite, test_building_defence_bonus);
+    SUITE_ADD_TEST(suite, test_building_defense_bonus);
     SUITE_ADD_TEST(suite, test_calculate_armor);
     SUITE_ADD_TEST(suite, test_natural_armor);
     SUITE_ADD_TEST(suite, test_magic_resistance);
diff --git a/src/spells/combatspells.c b/src/spells/combatspells.c
index 6d6b846c3..c088dde07 100644
--- a/src/spells/combatspells.c
+++ b/src/spells/combatspells.c
@@ -956,7 +956,7 @@ int sp_hero(struct castorder * co)
 
         if (df) {
             if (!(df->person[dt.index].flags & FL_COURAGE)) {
-                df->person[dt.index].defence += df_bonus;
+                df->person[dt.index].defense += df_bonus;
                 df->person[dt.index].flags = df->person[dt.index].flags | FL_COURAGE;
                 targets++;
                 --force;
@@ -1005,7 +1005,7 @@ int sp_berserk(struct castorder * co)
         if (df) {
             if (!(df->person[dt.index].flags & FL_COURAGE)) {
                 df->person[dt.index].attack += at_bonus;
-                df->person[dt.index].defence -= df_malus;
+                df->person[dt.index].defense -= df_malus;
                 df->person[dt.index].flags = df->person[dt.index].flags | FL_COURAGE;
                 targets++;
                 --force;
@@ -1064,7 +1064,7 @@ int sp_frighten(struct castorder * co)
         }
         if (!is_magic_resistant(mage, df->unit, 0)) {
             df->person[dt.index].attack -= at_malus;
-            df->person[dt.index].defence -= df_malus;
+            df->person[dt.index].defense -= df_malus;
             targets++;
         }
         --force;
@@ -1109,7 +1109,7 @@ int sp_tiredsoldiers(struct castorder * co)
         if (!(df->person[t.index].flags & FL_TIRED)) {
             if (!is_magic_resistant(mage, df->unit, 0)) {
                 df->person[t.index].flags = df->person[t.index].flags | FL_TIRED;
-                df->person[t.index].defence -= 2;
+                df->person[t.index].defense -= 2;
                 ++n;
             }
         }