from
The Collaborative International Dictionary of English v.0.48
Dorsal \Dor"sal\, a. [F. dorsal, LL. dorsalis, fr. L. dorsualis,
fr. dorsum back; cf. Gr. ?, ?, mountain ridge. Cf. {Dorse},
{Dorsel}, {Dosel}.]
1. (Anat.) Pertaining to, or situated near, the back, or
dorsum, of an animal or of one of its parts; notal;
tergal; neural; as, the dorsal fin of a fish; the dorsal
artery of the tongue; -- opposed to {ventral}.
[1913 Webster]
2. (Bot.)
(a) Pertaining to the surface naturally inferior, as of a
leaf.
(b) Pertaining to the surface naturally superior, as of a
creeping hepatic moss.
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{Dorsal vessel} (Zool.), a central pulsating blood vessel
along the back of insects, acting as a heart.
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