Zool. [f. URO-2 + CHORD sb.]
1. The notochord of ascidians and tunicates, regarded as corresponding to the primordial spinal column in vertebrates.
1877. Huxley, Anat. Inv. Anim., x. 595. The appendage … may be termed the urochord. Ibid., 598. A ganglion … passes along one side of the urochord to its extremity.
1880. A. Wilson, in Gentl. Mag. Jan., 46. Among the sea-squirts, the ‘urochord’ persists throughout life.
2. One of the Urochorda, a branch consisting of ascidians or tunicates.
1885. F. J. Bell, Comp. Anat., 313. Amphioxus has no external skeleton, nor have those Urochords that are tailed throughout life.
