diff --git a/man3/ptsname.3 b/man3/ptsname.3
index 3cfdd2fb2..5ae25c5e4 100644
--- a/man3/ptsname.3
+++ b/man3/ptsname.3
@@ -38,7 +38,7 @@ Glibc 2.23 and earlier:
 The
 .BR ptsname ()
 function returns the name of the slave pseudoterminal device
-corresponding to the master referred to by
+corresponding to the master referred to by the file descriptor
 .IR fd .
 .PP
 The