adv. rare–1. [f. L. umbōn-, umbo UMBO: cf. prec. and -AL, -LY.] In the manner of an umbo or shield-boss.
1654. Gayton, Pleas. Notes, IV. viii. 218. The Trunke hose, and Codpiece umbonically prominent, and significant as a Digitus Mercurialis.
