Keep out and Keep back

Keep out verb - Prevent from entering; shut out.

Keep back and keep out are semantically related in keep topic. In some cases you can use "Keep back" instead a verb "Keep out", when it comes to topics like repress.

Keep back verb - Keep under control; keep in check.

Keep out and keep back are semantically related in keep topic. Sometimes you can use "Keep out" instead a verb "Keep back", if it concerns topics such as repress.