UrochordataPronunciation: /ˌjʊərə(ʊ)kɔːˈdeɪtə/Definition of Urochordata noun Zoology a group of chordate animals that comprises the tunicates. Subphylum Urochordata, phylum Chordata Origin:modern Latin (plural), from uro-2 'tail' + ChordataUrochordata in other Oxford dictionaries Definition of Urochordata in the US English dictionary