diff --git a/src/vim.h b/src/vim.h
index 0dcadd1..9e34c2e 100644
--- a/src/vim.h
+++ b/src/vim.h
@@ -667,44 +667,46 @@
 #define MSG_HIST		0x1000
 
 /*
- * values for State
+ * Values for State.
  *
- * The lower bits up to 0x20 are used to distinguish normal/visual/op_pending
- * and cmdline/insert+replace mode.  This is used for mapping.  If none of
- * these bits are set, no mapping is done.
- * The upper bits are used to distinguish between other states.
+ * The lower bits up to 0x80 are used to distinguish normal/visual/op_pending
+ * /cmdline/insert/replace/terminal mode.  This is used for mapping.  If none
+ * of these bits are set, no mapping is done.  See the comment above do_map().
+ * The upper bits are used to distinguish between other states and variants of
+ * the base modes.
  */
-#define NORMAL		0x01	// Normal mode, command expected
-#define VISUAL		0x02	// Visual mode - use get_real_state()
-#define OP_PENDING	0x04	// Normal mode, operator is pending - use
+#define MODE_NORMAL	0x01	// Normal mode, command expected
+#define MODE_VISUAL	0x02	// Visual mode - use get_real_state()
+#define MODE_OP_PENDING	0x04	// Normal mode, operator is pending - use
 				// get_real_state()
-#define CMDLINE		0x08	// Editing command line
-#define INSERT		0x10	// Insert mode
-#define LANGMAP		0x20	// Language mapping, can be combined with
-				// INSERT and CMDLINE
+#define MODE_CMDLINE	0x08	// Editing the command line
+#define MODE_INSERT	0x10	// Insert mode, also for Replace mode
+#define MODE_LANGMAP	0x20	// Language mapping, can be combined with
+				// MODE_INSERT and MODE_CMDLINE
+#define MODE_SELECT	0x40	// Select mode, use get_real_state()
+#define MODE_TERMINAL	0x80	// Terminal mode
 
-#define REPLACE_FLAG	0x40	// Replace mode flag
-#define REPLACE		(REPLACE_FLAG + INSERT)
-#define VREPLACE_FLAG	0x80	// Virtual-replace mode flag
-#define VREPLACE	(REPLACE_FLAG + VREPLACE_FLAG + INSERT)
-#define LREPLACE	(REPLACE_FLAG + LANGMAP)
+#define MAP_ALL_MODES	0xff    // all mode bits used for mapping
 
-#define NORMAL_BUSY	(0x100 + NORMAL) // Normal mode, busy with a command
-#define HITRETURN	(0x200 + NORMAL) // waiting for return or command
-#define ASKMORE		0x300	// Asking if you want --more--
-#define SETWSIZE	0x400	// window size has changed
-#define ABBREV		0x500	// abbreviation instead of mapping
-#define EXTERNCMD	0x600	// executing an external command
-#define SHOWMATCH	(0x700 + INSERT) // show matching paren
-#define CONFIRM		0x800	// ":confirm" prompt
-#define SELECTMODE	0x1000	// Select mode, only for mappings
-#define TERMINAL        0x2000  // Terminal mode
+#define REPLACE_FLAG	0x100	// Replace mode flag
+#define MODE_REPLACE	(REPLACE_FLAG | MODE_INSERT)
+#define VREPLACE_FLAG	0x200	// Virtual-replace mode flag
+#define MODE_VREPLACE	(REPLACE_FLAG | VREPLACE_FLAG | MODE_INSERT)
+#define MODE_LREPLACE	(REPLACE_FLAG | MODE_LANGMAP)
+
+#define MODE_NORMAL_BUSY (0x1000 | MODE_NORMAL)
+				// Normal mode, busy with a command
+#define MODE_HITRETURN	(0x2000 | MODE_NORMAL)
+				// waiting for return or command
+#define MODE_ASKMORE	0x3000	// Asking if you want --more--
+#define MODE_SETWSIZE	0x4000	// window size has changed
+#define MODE_EXTERNCMD	0x5000	// executing an external command
+#define MODE_SHOWMATCH	(0x6000 | MODE_INSERT) // show matching paren
+#define MODE_CONFIRM	0x7000	// ":confirm" prompt
 #define MODE_ALL	0xffff
 
-#define MODE_MAX_LENGTH	4	// max mode length returned in mode()
-
-// all mode bits used for mapping
-#define MAP_ALL_MODES	(0x3f | SELECTMODE | TERMINAL)
+#define MODE_MAX_LENGTH	4	// max mode length used by get_mode(),
+				// including the terminating NUL
 
 // directions
 #define FORWARD			1
@@ -2484,7 +2486,6 @@
   /*
    * Avoid clashes between Perl and Vim namespace.
    */
-# undef NORMAL
 # undef STRLEN
 # undef FF
 # undef OP_DELETE