calyptra

[ kuh-lip-truh ]

noun

, Botany.

1. Also called cap. a hood or hoodlike part, as the lid of the capsule in mosses.
2. a root cap.

calyptra

/ kəˈlɪptrə; kəˈlɪpˌtreɪt /

noun

1. a membranous hood covering the spore-bearing capsule of mosses and liverworts
2. any hoodlike structure, such as a root cap

calyptra

/ kə-lĭp′trə /

1. In some bryophyte plants, a structure that covers the young sporophyte as it develops within the tissues of its gametophyte parent. The calyptra, which consists of a thickening of the archegonium walls, eventually breaks open as the spore capsule grows.
2. See root cap

Derived Forms

• calyptrate, adjective

Other Words From

• ca·lyp·trate [k, uh, -, lip, -treyt], adjective

Word History and Origins

Origin of calyptra¹

1745–55; < New Latin < Greek kalýptra veil, covering, equivalent to kalýp ( tein ) to veil, cover + -tra noun suffix

Word History and Origins

Origin of calyptra¹

C18: from New Latin, from Greek kaluptra hood, from kaluptein to cover

Example Sentences

The ripped-off piece of its birthplace often remains stuck to the top of the sporophyte and is called a calyptra.

From Scientific American

If not preserved in an envelope the calyptra and operculum are very apt to fall off and become lost.

From Project Gutenberg

Involucral leaves coalescent into an oblong truncate hairy tube, blended in our species with the calyptra; perianth none.

From Project Gutenberg

The calyptra or veil is remarkably small, smooth, and membranous.

From Project Gutenberg

D, capsules of Bartramia: i, with; ii, without the calyptra.

From Project Gutenberg