diff --git a/cloud/openstack/os_server.py b/cloud/openstack/os_server.py
index 0d0c5566f96..546e2b1644f 100644
--- a/cloud/openstack/os_server.py
+++ b/cloud/openstack/os_server.py
@@ -77,7 +77,7 @@ options:
    security_groups:
      description:
         - Names of the security groups to which the instance should be
-          added.  This may be a YAML list or a common separated string.
+          added. This may be a YAML list or a comma separated string.
      required: false
      default: None
    network: