Dictionary entry

Calyptra

Webster's Dictionary 1913

Ca‐lyp″tra (kȧ‐lĭp″trȧ), n. [NL., fr. Gr. καλύπτρα a covering for the head, fr. καλύπτειν to cover.] (Bot.) A little hood or veil, resembling an extinguisher in form and position, covering each of the small flasklike capsules which contain the spores of mosses; also, any similar covering body.