Uhlan is a military rank, the equivalent of which is used by the service organizations of different civilizations. In human origin, an uhlan was a skirmish fighter armed with a lance, and later, pistols. The term is of middle European origin.
As a grade, uhlan is an enlisted rank in a fighting organization, below a sergeant or corporal. In comparison to naval ranking systems, this rank is marginally equivalent to the naval crewman ranks.
This grade exists in some form in other rank arrangements, such as the Romulan Star Empire. Proconsul Neral joined the Romulan military, starting at this rank, before moving on to his political career. (TNG: "Unification II")