Webster's Revised Unabridged Dictionary · 1913

Gastrotricha

Gastrotricha , noun, plural

[New Latin, from Greek {not transcribed} belly + {not transcribed}, {not transcribed}, hair.]

(Zoology) A group of small wormlike animals, having cilia on the ventral side. The group is regarded as an ancestral or synthetic one, related to rotifers and annelids.