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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.
the mushroom-shaped plug of fibrin that fills the aperture in the endometrium made by the implanting blastocyst.
The plug of fibrin that covers the opening in the endometrium made by implantation of the blastocyst.
See also: operculum