protochordate: Meaning and Definition of

pro•to•chor•date

Pronunciation: (prō"tō-kôr'dāt), [key]
— n. Zool.
  1. any of the nonvertebrate chordates, as the tunicates, cephalochordates, and hemichordates.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.