There already was http://meta.pets.stackexchange.com/questions/712/fencing-or-containment , but this is with two different tags that mean sort of the same thing, but are used synonymously, especially as regards fencing.

containment and enclosure

For argument's sake, we also have cage, which is used synonymously with enclosure, especially as regards hutches.

I don't know if we should synonym these or not. Thoughts?