EnteropneustaEn`te*rop*neus"ta\, n. pl. [NL., fr. Gr. ? an intestine + ? to breathe.] (Zo["o]l.) A group of wormlike invertebrates having, along the sides of the body, branchial openings for the branchial sacs, which are formed by diverticula of the alimentary canal. Balanoglossus is the only known genus. See Illustration in Appendix.