diff --git a/man5/resolv.conf.5 b/man5/resolv.conf.5
index c1b3d017a..8ed958932 100644
--- a/man5/resolv.conf.5
+++ b/man5/resolv.conf.5
@@ -264,7 +264,7 @@ these options were removed in glibc 2.25.
 .TP
 .BR edns0 " (since glibc 2.6)"
 Sets
-.BR RES_USE_EDNSO
+.BR RES_USE_EDNS0
 in
 .IR _res.options .
 This enables support for the DNS extensions described in RFC\ 2671.