Otolith

Definitions

  • Webster's Revised Unabridged Dictionary
    • n Otolith (Anat) One of the small bones or particles of calcareous or other hard substance in the internal ear of vertebrates, and in the auditory organs of many invertebrates; an ear stone. Collectively, the otoliths are called ear sand and otoconite.
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Century Dictionary and Cyclopedia
    • n otolith A calcareous concretion within the membranous labyrinth of the ear. In fishes and fish-like vertebrates they are sometimes of great size. In higher animals otoliths are generally wanting or reduced to small particles or ear-dust. (See otoconium.) Among some common fishes the otolith decreases in size in the following order: cod, hake, haddock, whiting, conger, turbot, sole, gurnard, smelt, and trout. The concretions differ much in shape. In the conger the otolith is shaped like a sole, 1¼ inches long, ⅜ inch wide, and is thin and glassy. In the cod it is of the size of a horse-bean, and is curved on itself. The ear-stones of the American sheepshead are shaped like a tamarind-seed, and look like pieces of milky quartz. They are often carried in the pocket as “lucky stones.”
    • n otolith One of the proper otic bones of some animals, as certain fishes; an otosteon. See cuts under Esox and Python. Synonyms Otoliths, Otostea, Otoconia, and Otoconites are all concretions in the inmost ear; the two first-mentioned words are by some restricted to the large solid “ear-stones” of lower animals, while the latter two designate the small ones or very fine “eardust” of higher animals. They have properly no part in the bony structure of the ear, but a vibratory or concussive function in audition. But otolith and otosteon are sometimes applied to the internal ear-bones of fishes.
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Chambers's Twentieth Century Dictionary
    • Otolith a calcareous concretion within the membranous labyrinth of the ear
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Etymology

Webster's Revised Unabridged Dictionary
Oto-, + -lith, -lite,
Chambers's Twentieth Century Dictionary
Gr. ous, ōtos, ear.

Usage

In literature:

Tympanules: small openings covered by a membrane, having otoliths and serving as ears.
"Explanation of Terms Used in Entomology" by John. B. Smith
In others the ear cavity contains certain minute solid bodies, known as otoliths, which in the same way play upon the nerve fibres.
"The Beauties of Nature" by Sir John Lubbock
Simultaneously with the otolithic capsules, four rudimentary tentacles make their appearance between the four tentacles.
"The Romance of Natural History, Second Series" by Philip Henry Gosse
The Leydigian or nuchal organ is supposed to be auditory and to contain an otolith.
"Encyclopaedia Britannica, 11th Edition, Volume 9, Slice 6" by Various
These contain each a single concretionary otolith.
"Encyclopaedia Britannica, 11th Edition, Volume 7, Slice 7" by Various
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In news:

Their ' ear stones ' — or otoliths — reveal life histories through mineral layers.
Otolith 's entire raison d'etre is to provide consumers with fish that is environmentally responsible.
Their 'ear stones' — or otoliths — reveal life histories through mineral layers.
Seeking full-time Research Technician to assist with structural analysis of alewife otoliths.
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In science:

The nervous system may rely on inputs from e.g. muscle spindles, joint receptors, vestibular sensors in the inner ear (semicircular canals, otolithic organs), gravity receptors in the trunk, plus visual cues.
Review of Nonlinear Methods and Modelling
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