diff --git a/libguile/vectors.h b/libguile/vectors.h
index d479d1b80..77d6131bf 100644
--- a/libguile/vectors.h
+++ b/libguile/vectors.h
@@ -95,7 +95,6 @@ extern void scm_init_vectors (void);
 
 #if (SCM_DEBUG_DEPRECATED == 0)
 
-#define SCM_NVECTORP(x) (!SCM_VECTORP (x))
 extern SCM scm_vector_set_length_x (SCM vect, SCM len);
 
 #endif  /* SCM_DEBUG_DEPRECATED == 0 */