diff --git a/doc/lispref/control.texi b/doc/lispref/control.texi
index ecf616fc2be..34653d70565 100644
--- a/doc/lispref/control.texi
+++ b/doc/lispref/control.texi
@@ -525,7 +525,7 @@ core pattern can have the following forms:
 
 @table @code
 
-@item _
+@item _@r{ (underscore)}
 Matches any @var{expval}.
 This is also known as @dfn{don't care} or @dfn{wildcard}.
 
diff --git a/doc/lispref/strings.texi b/doc/lispref/strings.texi
index 3d8db985e9c..742ab76244d 100644
--- a/doc/lispref/strings.texi
+++ b/doc/lispref/strings.texi
@@ -1345,7 +1345,7 @@ given width, if specified.
 This flag converts the substituted text to upper case (@pxref{Case
 Conversion}).
 
-@item _
+@item _@r{ (underscore)}
 This flag converts the substituted text to lower case (@pxref{Case
 Conversion}).
 @end table