a. [f. Gr. ἄστομ-ος mouthless (f. ἀ priv. + στόμα, -ματ-, mouth) + -OUS.] Having no mouth, astomatous; applied chiefly in Bot. to those Mosses in which the urn does not open by the detachment of the operculum.
1857. Henfrey, Bot., § 319. In what are called Astomous Mosses there is no deciduous operculum.
1880. Gray, Bot. Text-Bk., 398. Astomous, without a stoma or mouth.
