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.

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]

operculum

/oper·cu·lum/ (o-per´ku-lum) pl. oper´cula   [L.]
1. a lid or covering.
2. the folds of pallium from the frontal, parietal, and temporal lobes of the cerebrum overlying the insula.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.

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.

operculum

[ōpur′kyoo͡ləm] pl. opercula, operculums
Etymology: L, lid
a lid or covering, such as the mucous plug that blocks the cervix of the gravid uterus or the temporal operculum of the cerebral temporal hemisphere that overlaps the insula as an extension of the superior surface of the temporal lobe. opercular, adj.

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]

operculum

A covering membrane, flap or lid of tissue, especially in the brain, or over an erupting tooth.

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.

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).

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]

operculum (ōpur´kūləm),

n a flap of tissue over a partially erupted or unerupted tooth, particularly a third molar. It may result in pericoronitis with inflammation of the flap tissue. See also pericoronitis.

operculum

pl. opercula [L.]
1. a lid or covering.
2. the folds of pallium from the frontal, parietal and temporal lobes of the cerebrum overlying the insula.
3. gill cover in a fish.

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.
References in periodicals archive ?
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.
The opercula for this study were collected ancillary to the biological samples gathered and analyzed by Stoner et al.
Very small fragments of former midden material, such as turban opercula and small chiton fragments were thinly scattered over the surface of the dunes surrounding the blowout where there had been none the previous year.
gariepinus were exposed to varying concentrations of aluminium phosphide and this manifested various effects on the behaviour of the fish which included graying of the epidermal layer of the skin, yellowish colouration of the operculum, fin and opercula movement and eventually death.
Penfield and Jasper in 1954 were the first ones to use intra operative interictal stimulation of hidden surfaces under the frontal and parietal opercula as well as recording the insula activity after temporal lobectomy (12).
Scales, otoliths, vertebrae, opercula, and subopercula were used to age pontic shad (Alosa pontica) in two recent studies that included the family Clupeidae [Yilmaz and Polat, 2002; Visnjic-Jeftic et ah, 2009]), yet no such comprehensive study has been completed for the American shad.
These behaviors, variously termed lowering of branchiostegals, raised opercula, gill-cover erection, and branchiostegal flaring, usually are associated with aggression and have arisen independently in multiple groups.
5-2 diameters, males with the ventral margin of the fixed cheliceral finger irregularly undulate, striate bristles of the flagellum complex indistinctly striate with apical and subapical bristles broad and flattened, and females with roughly triangular genital opercula, with parallel medial margins.
Since the date of birth of these juveniles was known, the analyses focused on whether the ring marks of the scales, sagittae and opercula or the circuli of the scales could be used to age them.
The animals were undamaged, with normal, attached opercula and no visible shell.
which had opercula in place, indicating that these animals had died recently in situ by desiccation, 47 shells of Cipangopaludina sp.