eccentric (n.) Look up eccentric at Dictionary.com
early 15c., "eccentric circle or orbit," originally a term in Ptolemaic astronomy, "circle or orbit not having the Earth precisely at its center," from Middle French eccentrique and directly from Medieval Latin eccentricus (noun and adjective), from Greek ekkentros "out of the center" (as opposed to concentric), from ek "out" (see ex-) + kentron "center" (see center (n.)). Meaning "odd or whimsical person" first attested 1832.
eccentric (adj.) Look up eccentric at Dictionary.com
1550s, from Middle French eccentrique and directly from Medieval Latin eccentricus (noun and adjective; see eccentric (n.)). Figurative sense of "odd, whimsical" first recorded 1620s.