from The American Heritage® Dictionary of the English Language, 4th Edition
- n. A small sac.
- n. The smaller of two membranous sacs in the vestibule of the inner ear.
from Wiktionary, Creative Commons Attribution/Share-Alike License
- n. The smallest chamber of the membranous labyrinth of the ear.
from the GNU version of the Collaborative International Dictionary of English
- n. A little sac; specifically, the sacculus of the ear.
from The Century Dictionary and Cyclopedia
- 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.
from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
- 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).
The saccule is the smaller of the two vestibular sacs; it is globular in form, and lies in the recessus sphæricus near the opening of the scala vestibuli of the cochlea.
The saccule is a bed of sensory cells situated in the inner ear.
Lying above and forward are the utricle and the structures developed from it, and lying below and behind are the saccule and the structures developed from it.
(The structure is similar to the saccule and its outgrowths.)
In consequence of this an apparently new apex has been formed by the growing downward of the right saccule, and the original apex, with the appendix attached, is pushed over to the left toward the ileocolic junction.
In the second type, the conical cecum has become quadrate by the growing out of a saccule on either side of the anterior longitudinal band.
The fourth type is merely an exaggerated condition of the third; the right saccule is still larger, and at the same time the left saccule has become atrophied, so that the original apex of the cecum, with the vermiform process, is close to the ileocolic junction, and the anterior band courses medialward to the same situation.
The three longitudinal bands still start from the base of the vermiform process, but they are now no longer equidistant from each other, because the right saccule has grown between the anterior and posterolateral bands, pushing them over to the left.
The vestibular branches are distributed to the utricle, saccule, and semicircular ducts.