diff --git a/include/fmt/core.h b/include/fmt/core.h
index 45bf19bb..1d31c436 100644
--- a/include/fmt/core.h
+++ b/include/fmt/core.h
@@ -223,8 +223,8 @@
 #ifndef FMT_EXTERN_TEMPLATE_API
 #  define FMT_EXTERN_TEMPLATE_API
 #endif
-#ifndef FMT_INSTANTIATION_DEF_API
-#  define FMT_INSTANTIATION_DEF_API FMT_API
+#ifndef FMT_INSTANTIATION_DECL_API
+#  define FMT_INSTANTIATION_DECL_API FMT_API
 #endif
 
 #ifndef FMT_HEADER_ONLY