Board Thread:Suggestions forum/@comment-34241117-20180328015111/@comment-31507215-20180328042358

I think that, in the mod, Uruk-hai are simply called "Uruks" (and I think it has been argued about before) so "Uruk", without anything before it, is synonymous with "Uruk-hai".

Like Recneps said, however, there are also Black Uruks (which can be hired from Mordor captains) and Gundabad Uruks (which can be hired from Gundabad captains).