What is "urochord"

Urochord \U"ro*chord\, n. [2d uro- + chord.] (Zo["o]l.) The central axis or cord in the tail of larval ascidians and of certain adult tunicates. [Written also urocord.]

n. 1 (context biology English) a notochord that is limited to the caudal region; especially in the Urochordata 2 any marine organism of the Urochordata

1. n. primitive marine animal having a saclike unsegmented body and a urochord (a notochord) conspicuous in the larva [syn: tunicate, urochordate]

2. a notochord of a larval tunicate typically confined to the caudal region