diff --git a/src/xdisp.c b/src/xdisp.c
index 7d31813a57e..baf181cba1c 100644
--- a/src/xdisp.c
+++ b/src/xdisp.c
@@ -28133,7 +28133,7 @@ store_mode_line_string (const char *string, Lisp_Object lisp_string,
 
 DEFUN ("format-mode-line", Fformat_mode_line, Sformat_mode_line,
        1, 4, 0,
-       doc: /* Format a string out of a mode line format specification.
+       doc: /* Return a string formatted according to mode-line format specification.
 First arg FORMAT specifies the mode line format (see `mode-line-format'
 for details) to use.