- Also called cap. a hood or hoodlike part, as the lid of the capsule in mosses.
- a root cap.
Origin of calyptra
1745–55; < New Latin < Greek kalýptra veil, covering, equivalent to kalýp(tein) to veil, cover + -tra noun suffix
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
Examples from the Web for calyptra
The calyptra is half-cleft, and the lid conical and shortly beaked.
The calyptra (fig. 24) is half-cleft (dimidiate) and very hairy.
Calyptra membranous, oval, longer or shorter than the involucre.
Calyptra minute, lacerate, persistent at the base of the capsule.
The calyptra or veil is remarkably small, smooth, and membranous.Lachesis Lapponica
Carl von Linn
- a membranous hood covering the spore-bearing capsule of mosses and liverworts
- any hoodlike structure, such as a root cap
C18: from New Latin, from Greek kaluptra hood, from kaluptein to cover
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
- 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.
- See root cap.
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