diff --git a/src/network/network_internal.h b/src/network/network_internal.h
--- a/src/network/network_internal.h
+++ b/src/network/network_internal.h
@@ -93,8 +93,6 @@ enum NetworkLanguage {
 	NETLANG_COUNT
 };
 
-#define VARDEF extern
-
 extern NetworkPlayerInfo _network_player_info[MAX_PLAYERS];
 
 extern uint32 _frame_counter_server; // The frame_counter of the server, if in network-mode
diff --git a/src/openttd.h b/src/openttd.h
--- a/src/openttd.h
+++ b/src/openttd.h
@@ -5,10 +5,6 @@
 #ifndef OPENTTD_H
 #define OPENTTD_H
 
-#ifndef VARDEF
-#define VARDEF extern
-#endif
-
 enum GameModes {
 	GM_MENU,
 	GM_NORMAL,
diff --git a/src/variables.h b/src/variables.h
--- a/src/variables.h
+++ b/src/variables.h
@@ -5,6 +5,10 @@
 #ifndef VARIABLES_H
 #define VARIABLES_H
 
+#ifndef VARDEF
+#define VARDEF extern
+#endif
+
 /* Amount of game ticks */
 VARDEF uint16 _tick_counter;