diff --git a/share/man/man9/sleep.9 b/share/man/man9/sleep.9
index f371652efc8d..a52f4d5d2df2 100644
--- a/share/man/man9/sleep.9
+++ b/share/man/man9/sleep.9
@@ -43,7 +43,7 @@
 .Ft int
 .Fn tsleep "void *ident" "int priority" "const char *wmesg" "int timo"
 .Ft int
-.Fn msleep "void *ident" "mtx_t *mtx" "int priority" "const char *wmesg" "int timo"
+.Fn msleep "void *ident" "struct mtx *mtx" "int priority" "const char *wmesg" "int timo"
 .Ft int
 .Fn asleep "void *ident" "int priority" "const char *wmesg" "int timo"
 .Ft int