diff --git a/src/core/ngx_string.c b/src/core/ngx_string.c
index 0e33e38..62dde82 100644
--- a/src/core/ngx_string.c
+++ b/src/core/ngx_string.c
@@ -90,7 +90,7 @@
  *
  *  reserved:
  *    %t                        ptrdiff_t
- *    %S                        null-teminated wchar string
+ *    %S                        null-terminated wchar string
  *    %C                        wchar
  */