Eccentric  —adj. 1 odd or capricious in behaviour or appearance. 2 (also excentric) a not placed, not having its axis placed, centrally. B (often foll. By to) (of a circle) not concentric (to another). C (of an orbit) not circular. —n. 1 eccentric person. 2 disc at the end of a shaft for changing rotatory into backward-and-forward motion.  eccentrically adv. Eccentricity n. [greek: related to *centre]