operculum

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operculum

 [o-per´ku-lum] (L.)
1. a lid or covering.
2. the folds of pallium from the frontal, parietal, and temporal lobes of the cerebrum overlying the insula. adj., adj oper´cular.
dental operculum the hood of gingival tissue overlying the crown of an erupting tooth.
trophoblastic operculum the plug of trophoblast that helps close the gap in the endometrium made by the implanting blastocyst.
Miller-Keane Encyclopedia and Dictionary of Medicine, Nursing, and Allied Health, Seventh Edition. © 2003 by Saunders, an imprint of Elsevier, Inc. All rights reserved.

o·per·cu·lum

, gen.

o·per·cu·li

, pl.

o·per·cu·la

(ō-per'kyū-lŭm, -lī, -lă),
1. Anything resembling a lid or cover.
2. In anatomy, the portions of the frontal (operculum frontale [TA], frontal operculum [TA]), parietal (operculum parietale [TA], parietal operculum [TA]), and temporal (operculum temporale [TA], temporal operculum [TA]) lobes bordering the lateral sulcus and covering the insula.
3. In parasitology, the lid or caplike cover of the shell opening of operculated freshwater snails in the subclass Prosobranchiata, and of the eggs of certain trematode and cestode parasites.
4. The attached flap in the tear of retinal detachment.
5. The mucosal flap partially or completely covering an unerupted tooth.
[L. cover or lid, fr. operio, pp. opertus, to cover]
Farlex Partner Medical Dictionary © Farlex 2012

operculum

(ō-pûr′kyə-ləm)
n. pl. opercu·lums or opercu·la (-lə)
1. Something resembling a lid or cover.
2. The portions of the frontal, parietal, and temporal lobes covering the insula.
3. A bit of mucus sealing the endocervical canal of the uterus after conception.
4. The attached flap in cases of torn retinal detachment.

o·per′cu·lar (-lər) adj.
The American Heritage® Medical Dictionary Copyright © 2007, 2004 by Houghton Mifflin Company. Published by Houghton Mifflin Company. All rights reserved.

o·per·cu·lum

, pl. opercula (ō-pĕr'kyū-lŭm, -lă) [TA]
1. Anything resembling a lid or cover.
2. [TA] anatomy The portions of the frontal, parietal, and temporal lobes bordering the lateral sulcus and covering the insula.
3. Mucus sealing the endocervical canal of the uterus after conception has taken place.
4. parasitology The lid or caplike cover of the shell opening of operculated freshwater snails in the subclass Prosobranchiata, and of the eggs of certain trematode and cestode parasites.
5. The attached flap in the tear of retinal detachment.
6. The mucosal flap partially or completely covering a partially erupted tooth.
[L. cover or lid, fr. operio, pp. opertus, to cover]
Medical Dictionary for the Health Professions and Nursing © Farlex 2012

operculum

A covering membrane, flap or lid of tissue, especially in the brain, or over an erupting tooth.
Collins Dictionary of Medicine © Robert M. Youngson 2004, 2005

operculum

  1. the lid of a MOSS capsule.
  2. a hard bony flap covering the gills of fishes.
  3. the plate of exoskeletal material on the foot of a gastropod mollusc with which it closes off the entrance to the shell.
Collins Dictionary of Biology, 3rd ed. © W. G. Hale, V. A. Saunders, J. P. Margham 2005

operculum 

A flap of detached retina which projects forward, or is totally free in the vitreous. It can happen as a result of a retinal tear (break).
Millodot: Dictionary of Optometry and Visual Science, 7th edition. © 2009 Butterworth-Heinemann

o·per·cu·lum

, pl. opercula (ō-pĕr'kyū-lŭm, -lă) [TA]
1. [TA] The mucosal flap partially or completely covering an unerupted tooth.
2. Anything resembling a lid or cover.
[L. cover or lid, fr. operio, pp. opertus, to cover]
Medical Dictionary for the Dental Professions © Farlex 2012
References in periodicals archive ?
Opercula of two gastropods from the Lilydale Limestone (Early Devonian) of Victoria, Australia.
Shape of Germination Pore and/or Opercula. Typically, the germination pores and opercula are not circular but rather are elliptical or broadly elliptical.
The clarity and readability of statoliths are often far higher than those of opercula (Fisher 2015, Hollyman 2017).
Although current methods for age determination of tautog are based on opercula and otoliths, multiple structures have been used to age other fish species, including opercula, otoliths, vertebrae, fin rays, fin spines, and scales (Beamish and McFarlane, 1987; Panfili et al., 2002).
Laboratory studies could easily be designed to determine normal gut-passage times for humpback and broad whitefish, survival rates of clams and snails during gut passage, size and temperature effects on survival rates, and differential survival rates of snails with opercula versus those without.
The archaeological assemblage of Babjarrimannos Midden 2 was dominated by chiton shell and turban opercula. Small quantities of other marine molluscs occurred in the site, including baler, bivalves and Terebralia palustra.
Two other groups have found poor language skills associated with anomalous parietal opercula. In a new sample of dyslexic college students, those with type III patterns had worse scores on a number of auditory and phonological tests, in particular one that required them to blend two phonemes together (Eckert & Leonard, 2001).
There are a limited number of published studies using opercula as an aging technique for channeled whelk in southern New England (Wood 1979, Peemoeller & Stevens 2013, Wilcox 2013).
Timbal cover very broad, dumbbell' shaped, laterally hollow, concealed by opercula apically, gray to chocolate brown, timbal with curved long ribs (Fig.
In this study, we compared the precision of age estimates obtained from sagittal otoliths, vertebrae, scales, and opercula as structures for the age determination of American shad.
gracilis, arguing that Dipleuron and Lovenella would be distinct because of "differences in the morphology of their opercula" (Calder, 1991: 3).