diff --git a/man2/sigaltstack.2 b/man2/sigaltstack.2
index 3d7458dd4..4e2975765 100644
--- a/man2/sigaltstack.2
+++ b/man2/sigaltstack.2
@@ -130,7 +130,7 @@ Either \fIss\fP or \fIoss\fP is not NULL and points to an area
 outside of the process's address space.
 .TP
 .B EINVAL
-\fIss\fP is not NULL and the \fPss_flags\fP field contains
+\fIss\fP is not NULL and the \fIss_flags\fP field contains
 a non-zero value other than
 .BR SS_DISABLE .
 .TP