Concave /(kŏṉ*kā*v" [or] kŏn"-; 277)/

1. 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.
2. Hollow; void of contents. [R.]

   As concave . . . as a worm-eaten nut.

1. A hollow; an arched vault; a cavity; a recess.

   Up to the fiery concave towering hight.

2. A curved sheath or breasting for a revolving cylinder or roll. (Mech.)

imp. & p. p. concaved; p. pr. & vb. n. Concaving

1. To make hollow or concave.