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1. The structure formed by invagination of the embryonic ectodermal tissue that develops into the inner ear.
2. A statocyst.

o′to·cys′tic adj.
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.


1. (Zoology) another name for statocyst
2. (Zoology) the embryonic structure in vertebrates that develops into the inner ear in the adult
ˌotoˈcystic adj
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014


(ˈoʊ tə sɪst)

2. one of a pair of pouches that form in the front part of the embryo by the infolding of a thickened area of ectoderm.
o`to•cys′tic, adj.
Random House Kernerman Webster's College Dictionary, © 2010 K Dictionaries Ltd. Copyright 2005, 1997, 1991 by Random House, Inc. All rights reserved.
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References in periodicals archive ?
After the development of the otic vesicle, the otocyst gives rise to the mature IE structures, including the vestibular system in the dorsal plane and the auditory system in the ventral plane.
The semicircular canals and their neural elements are derived from the two prominences of the otocyst, the horizontal and vertical canal pouches.
The fact that the cochlea and vestibule show no malformations suggests that the defect develops at a stage of development that is more advanced than the otocyst stage [5].
At E9.5, Pax2 was expressed throughout the epithelium of the otic otocyst, but it was more concentrated in the centro-medial area next to the neural tube.
Cocultures of mammalian stem cells with the chick otocyst and its stromal cells produced hair cell-like cells with stereocilia-like protrusions (Jeon et al.; Oshima et al., 2010).
In vertebrates, this organ is called an otocyst with an otolith or otoconia (Budelmann, 1988).
(1) The endolymphatic sac develops from the otocyst and lies between the internal auditory canal and sigmoid sinus.
Let's see what can be done with their names: SCOTTY ta1 = otocyst SCOTTY ta2 = boycotts, cryostat, otocysts MOORE tp = Romeo MOORE ta1 = boomer, mooner, moored, morose, roomie MOORE ta2 = bedroom, boredom, doormen, groomed, hormone, promote SCOTTY MOORE ta5 = cytophotometries SCOTTY MOORE ta6 = spectrophotometry BILL ta1 = billy, brill, libel BILL ta2 = billet, billow, glibly, liable BLACK ta1 = blacks BLACK ta2 = backlit, backlog, becloak, layback BILL BLACK ta3 = blackballing FONTANA ta1 = nonfatal FONTAN A ta3 = nonfactual FLOYD ta1 = fondly FLOYD ta2 = dropfly, twyfold CRAMER ta1 = charmer, creamer, marcher CRAMER ta2 = carmaker, creamery, screamer
A rudimentary otocyst is used to define incomplete milimetric representations of the otic capsule (round or ovoid in shape) without an IAC (Figure 3).
[1,2] Should inner ear development be interrupted between the fourth and fifth weeks of gestation after differentiation of the auditory placode into the otocyst, but before division of the latter into the primordium of the cochlea, vestibule, and semicircular canals--a "common cavity" forms that has no internal architecture (figure).
The otocysts contain smaller otoliths, and they are irregular in shape; the heart tube is attached by a thin strand of cells to the pericardial wall; and blood cells pool on the ventral side of the embryo at the level of the hindbrain and along the length of the tail.