A fractional monetary unit of several countries: El Salvador and Sao Tome and Principe and Brazil and Argentina and Bolivia and Colombia and Cuba and the Dominican Republic and Ecuador and El Salvador and Guatemala and Honduras and Mexico and Nicaragua and Peru and the Philippines and Portugal
(a.) Hollow and curved or rounded; vaulted; -- said of the interior of a curved surface or line, as of the curve of the of the inner surface of an eggshell, in opposition to convex; as, a concave mirror; the concave arch of the sky.
(a.) Hollow; void of contents.
(n.) A hollow; an arched vault; a cavity; a recess.
(n.) A curved sheath or breasting for a revolving cylinder or roll.