- A thin leaf, plate, disk, wafer.
* * *1. [TA] A thin sheet or layer (such as occurs in compact bone) or sublayer. 2. A preparation in the form of a medicated gelatin disk, used as a means of making local applications to the conjunctiva in place of solutions. SYN: discus [TA], disk (2) [TA]. [L. dim. of lamina, plate, leaf]- annulate lamellae several pairs of parallel, smooth membranes, each pair containing regularly spaced pores resembling those of the nuclear envelope; they occur in germ cells, embryonic cells, and neoplastic cells.- articular l. the compact layer of bone on its articular surface that is firmly attached to the overlying articular cartilage.- concentric l. one of the concentric tubular layers of bone surrounding the central canal in an osteon. SYN: haversian l..- cornoid l. a narrow vertical column of parakeratosis in the epidermal stratum corneum; characteristic of porokeratosis.- elastic l. a thin sheet or membrane composed of elastic fibers; distinguished from elastic membrane, which usually refers to a condensed mass of fibers, as in an artery, whereas an elastic l. may be a looser elastic layer such as found in a vein or the respiratory tract.- enamel l. an organic defect in enamel; a thin, leaflike structure that extends from the enamel surface toward the dentinoenamel junction.- ground l. SYN: interstitial l..- interstitial l. one of the lamellae of partially resorbed osteons occurring between newer, complete osteons. SYN: ground l., intermediary system, intermediate l..- tympanic l. (of osseous spiral lamina) [TA] the thinner of two plates of bone, incompletely separated from each other by canals for peripheral fibers from the spiral (cochlear) ganglion, that together comprise the osseous spiral lamina; this plate lies on the side of the scala tympani, forming a portion of its wall. SYN: l. tympanica (laminae spiralis ossei) [TA].- vestibular l. (of osseous spiral lamina) [TA] the thicker of two plates of bone, incompletely separated from each other by canals for peripheral fibers from the spiral (cochlear) ganglion, that together comprise the osseous spiral lamina; this plate lies on the side of the scala vestibuli; a thickening of the periosteum, the spiral limbus, is attached to the vestibular l. within the cochlear duct. SYN: l. vestibularis (laminae spiralis ossei) [TA].
* * *1) an organ, process, or part resembling a plate: asa) one of the bony concentric layers surrounding the haversian canals in boneb ) (1) one of the incremental layers of cementum laid down in a tooth (2) a thin sheetlike organic structure in the enamel of a tooth extending inward from a surface crack2) a small medicated disk prepared from gelatin and glycerin for use esp. in the eyes <lamellae of atropine>
* * *n. (pl. lamellae)1. a thin layer, membrane, scale, or plate-like tissue or part. In bone tissue, lamellae are thin bands of calcified matrix arranged concentrically around a Haversian canal.2. a thin gelatinous medicated disc used to apply drugs to the eye. The disc is placed on the eyeball; the gelatinous material dissolves and the drug is absorbed.
* * *la·mel·la (lə-melґə) gen. and pl. lamelґlae [L., dim. of lamina] 1. a thin leaf or plate, as of bone. 2. a medicated disk or wafer prepared from gelatin, glycerin, and distilled water, and containing a small quantity of an alkaloid, to be inserted under the eyelid. 3. gill (def. 2).
Medical dictionary. 2011.