diff --git a/libguile/scm.h b/libguile/scm.h
index 180b40159..4156d1612 100644
--- a/libguile/scm.h
+++ b/libguile/scm.h
@@ -1,7 +1,7 @@
 #ifndef SCM_SCM_H
 #define SCM_SCM_H
 
-/* Copyright 1995-2004,2006-2015,2017-2019,2023
+/* Copyright 1995-2004,2006-2015,2017-2019,2023,2025
      Free Software Foundation, Inc.
 
    This file is part of Guile.
@@ -452,7 +452,7 @@ typedef uintptr_t scm_t_bits;
 #define scm_tc3_cons	 	 0
 #define scm_tc3_struct    	 1
 #define scm_tc3_int_1		 (scm_tc2_int + 0)
-#define scm_tc3_unused		 3
+#define scm_tc3_forwarded	 3
 #define scm_tc3_imm24		 4
 #define scm_tc3_tc7_1		 5
 #define scm_tc3_int_2		 (scm_tc2_int + 4)