The Collaborative International Dictionary
Uro-
Uro- \U"ro-\ A combining form fr. Gr. o'y^ron, urine.
Uro-
Uro- \U"ro-\ A combining form from Gr. o'yra`, the tail, the caudal extremity.
Douglas Harper's Etymology Dictionary
uro-
word-forming element meaning "urine," from comb. form of Greek ouron "urine" (see urine).
Wiktionary
uro-
Etymology 1 pre. urine; relating to urine Etymology 2
pre. urochord or the Urochordata; having a tail.