1 definition by baconfeet
UN-BOYFRIEND. Pronounced EWE-BEE. For a commitment-phobic woman, a UB is a man she is dating but she does not want anyone calling him her "boyfriend." She is often dating (and enjoying) several UBs at once. Of the ilk of friends with benefits or fuck buddies.
Girl_One: She has so many boyfriends, doesn't she?
Girl_Two: Naw, those are her UB's, she's just a cougar who can't commit.
Girl_Two: Naw, those are her UB's, she's just a cougar who can't commit.
by baconfeet June 1, 2007