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(la-mel'a) plural.lamellae [L., a little plate]
1. A thin layer, sheet, or plate.
2. A medicated disk of gelatin inserted under the lower eyelid and against the eyeball; used as a local application to the eye.

bone lamella

Plates of collagen fibers, 3 to 7 µm thick, found in secondary (mature, adult) bone and surrounded by cementing substance, the mineralized bone matrix. Some lamellae are parallel to each other. Other lamellae are aligned concentrically around a vascular canal — a structure known as a haversian system or osteon.

circumferential lamella

A layer of bone that underlies the periosteum, encircling the medullary cavity.

concentric lamella

One of the cylindrical plates of bone surrounding a haversian canal. Synonym: haversian l

enamel lamella

Microscopic cracks or calcification imperfections in the enamel surface of a tooth. They may be shallow or extend into the underlying dentin and occur as a developmental defect or a microfracture caused by temperature change or shearing forces.

ground lamella

Interstitial lamella.

haversian lamella

Concentric lamella.

interstitial lamella

The bone lamella filling the irregular spaces within the haversian system. Synonym: ground l.

medullary lamella

An osseous lamella surrounding and forming the wall of the marrow cavity of long bones.

periosteal lamella

The bone lamella next to and parallel with the periosteum, forming the external portion of bone.

triangular lamella

The small fibrous lamina between the choroid plexuses of the third ventricle of the brain.

vitreous lamella

Bruch's membrane.
References in periodicals archive ?
The lamellar structure consists of crystalline lamellae and the amorphous domain between lamellae.
Blood congestion, or even an aneurysm may be resulted due to an increased blood flow inside the lamellae causing the dilation of the marginal filaments, are in agreement with Martinez et al.
Fusion and clubbing of secondary lamellae were observed in fish gills exposed to 2ppm of BPA.
Stage Histopathologic alterations in the gills I Hypertrophy and hyperplasia of gill epithelium Sanguineous congestion Dilation of marginal vascular channels Lifting of respiratory epithelium Fusion and disorganisation of secondary gill lamellae Shortening of secondary lamellae Leukocyte infiltration of gill epithelium Aggregation of cells of the primary lamella II Haemorrhage and rupture of lamellar epithelium Hypertrophy and hyperplasia of mucous cells Empty mucous cells or their disappearance Hypertrophy and hyperplasia of chloride cells III Lamellar aneurism Necrosis and cell degeneration Lamellar telangiectasis Table 2.
In this frame, the authors highlighted the lack of any copulatory lamella in the internal sac of Copris, and the presence of two well differentiated accessory lamellae, named (according to the nomenclature created by Binaghi et al) "parietal accessory lamella" and "(conic) external lamella".
They showed that the cascade of events culminating in the condensation of the reflectins causes the osmotic pressure inside the lamellae to change drastically due to the expulsion of water, which shrinks and dehydrates the lamellae and reduces their thickness and spacing.
The diffusion of oxygen in to blood took place at the surface of thin walled gill lamellae that's why any change in fish due to toxicity is first detected through gills (Fig.
The disintegration of cementite lamellae became more pronounced with increasing number of cycles (Fig.
The companies said they haven't received any complaints or reports of side effects "directly attributed" to the flakes, called lamellae.
Indeed, as the lamellae break into smaller elements and spheroidize, the hardness drops (Krauss, 2005).