noun Botany.
- Also called cap. a hood or hoodlike part, as the lid of the capsule in mosses.
- a root cap.
noun botany
- a membranous hood covering the spore-bearing capsule of mosses and liverworts
- any hoodlike structure, such as a root cap
- 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.