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n. A small sac.

n. The smaller of two membranous sacs in the vestibule of the inner ear.

n. The smallest chamber of the membranous labyrinth of the ear.

n. A little sac; specifically, the sacculus of the ear.

n. A sac or cyst; especially, a little sac; a cell; a sacculus. Specifically

n. In anatomy, the smaller of two sacs in the vestibule of the membranous labyrinth of the ear, situated in the fovea hemispherica, in front of the utricle, connected with the membranous canal of the cochlea by the canalis reuniens, and prolonged in the aquæductus vestibuli to a pyriform dilatation, the saccus endolymphaticus.

n. Synonyms See sac.

n. a small sac or pouch (especially the smaller chamber of the membranous labyrinth)

"The tube that in land vertebrates developed from the saccule is the cochlea (kok'lee-uh; "snail-shell" L), which is a spiral structure that does indeed have a close resemblance to a snail shell, except that its width does not narrow as it approaches its central apex, but remains constant (see illustration, p. 253)."

sac   

saccule of the larynx    vestibular saccule    utricle