Definition:Lamina

Definition

A lamina is an ideal of a (rigid) body embedded in ordinary space such that one of its dimensions is infinitesimal.

That is, its thickness can be considered to be uniform and positive, but small enough to be ignored.

Such a lamina can be interpreted as a body which is all surface.

Thus it has area and (area mass) density but zero thickness.

Uniform Lamina

A uniform lamina is a lamina whose (area mass) density is constant.

Linguistic Note

The word lamina derives from the Latin for thin piece of metal, wood, or marble, or plate, leaf, or layer.

Hence the plural of lamina is properly laminae, although the form laminas can often be seen.

Sources

• 1989: Ephraim J. Borowski and Jonathan M. Borwein: Dictionary of Mathematics ... (previous) ... (next): lamina
• 1998: David Nelson: The Penguin Dictionary of Mathematics (2nd ed.) ... (previous) ... (next): lamina
• 2008: David Nelson: The Penguin Dictionary of Mathematics (4th ed.) ... (previous) ... (next): lamina
• 2014: Christopher Clapham and James Nicholson: The Concise Oxford Dictionary of Mathematics (5th ed.) ... (previous) ... (next): lamina