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Relating to an operculum.


Relating to an operculum.


(ō-pĕr′kū-lŭm) plural.opercula [L., a cover]
1. Any lid or covering.
2. The narrow opening at the top of the thoracic cage bordered by the sternum and first ribs.
3. The plug of mucus that fills the opening of the cervix on impregnation.
4. The convolutions of the cerebrum, the margins of which are separated by the lateral cerebral (sylvian) fissure. The opercula cover the insula. opercular (ō-pĕr′kū-lăr), adjective

dental operculum

The soft tissue overlying the crown of a partially erupted tooth.

trophoblastic operculum

The plug of fibrin that covers the opening in the endometrium made by implantation of the blastocyst.
References in periodicals archive ?
Head with 2 dark oblique bars extending posteriorly below orbit, 1 or 2 additional dark bars over cranium and opercular flap.
We feel that the stretch of the frontotemporal opercular fibers from acute hydrocephalus caused this syndrome and perhaps tolerance for this was lessened by previous radiation treatment in her youth.
IV Anestesia profunda Perda total de tonus muscular; perda total de equilibrio; batimento opercular lento, porem regular.
Transport processes in isolated teleost epithelio: opercular epithelium and urinary bladder.
Cephalic neuromasts: supraorbital 3 + 3, parietal 1, anterior rostral 1, posterior rostral 1, infraorbital 1 + 16 + 1, preorbital 3, otic 1, post-otic 2, supratemporal 1, median opercular 1, ventral opercular 2, preopercular 2 + 4, mandibular 4 + 2, lateral mandibular 3.
QC3, quantification code 3, identified to family: basi-branchial, basioccipital, basipterygium, ceratohyal, coracoid, ethmoid, ectopterygoid, epihyal, exoccipital, frontal, hyomandibular, interhyal, interopercular, lacrimal, lower hypohyal, opercular, opisthotic, otolith, palatine, prefrontal,' preopercular, prootic, pterotic, supracleithrum, scapula, supraoccipital, sphenotic, symplectic, urohyal, upper hypohyal.
Gustatory hallucinations have been found to originate from the parietal opercular region.
Larger larvae were distinguished by relevant morphological features, including the development of the opercular complex and head spination, meristics, and pigmentation pattern.
Additionally to the above the genus Papiliolebias is characterized by: urohyal, dorsal process branched (also in some species of Pituna); third epibranchial, uncinate process, forming an angle of 45-60[degrees] with distal process (also in rivulines but not in plesiolebi-asines); posttemporal, ventral process present; opercular region with regular reticulate pattern formed by iridescent colour on middle of scales contrasting with dark orangish brown pigment along entire scale margins (also in Pituna); and humeral region with iridescent blotch (also in Pituna) (Costa 2011).