How check if a post belong to a given taxonomy

That’s not quite it (at least not in the way I understand the question, which is similar to mine).

How would you determine if a specific post belongs to a particular taxonomy? This would be in the single-post template, not in an archive, so is_tax wouldn’t work here. It would be more along the lines of in_tax (like in_category), but there’s no such tag.

I think this is more what I was looking for (I should have said “taxonomy term” instead of just “taxonomy”).

http://wphit.com/lookup/2010/03/is_object_in_term/

Thanks, though!