concentric engine

A name for the rotary. engine (q. v.). concentric operculum, 8. Zool. ( of a univalve shell): An operculum which increases equally all around, and has its nucleus central or subcentral. Examples-Paludina and Ampullar i a. căn-çen-tric-al-ly, adv. [Eng. concentrical; -ly.] So as to po e the same center. con-çen'-tric-āte, v. t. [Eng. concentric; -ate.] To concentrate. ( Lit. & fig.) "Let them knit and concentric ate their beams."-Culver well: Light of Nations, 100. ( Latham .)