5. Deviating from stated methods, usual practice, or established forms or laws; deviating from an appointed sphere or way; departing from the usual course; irregular; anomalous; odd; as, eccentric conduct. This brave and eccentric young man. He shines eccentric, like a comet's blaze. (Savage) eccentric anomaly.
(Science: astronomy) The whole apparatus, strap, and other parts, by which the motion of an eccentric is transmitted, as in the steam engine. A cogwheel set to turn about an eccentric axis used to give variable rotation. Eccentric hook or gab, a hook-shaped journal box on the end of an eccentric rod, opposite the strap. Eccentric rod, the rod that connects as eccentric strap with any part to be acted upon by the eccentric. Eccentric sheave, or eccentric pulley, an eccentric. Eccentric strap, the ring, operating as a journal box, that encircles and receives motion from an eccentric; called also eccentric hoop.
3. (Science: astronomy) in the ptolemaic system, the supposed circular orbit of a planet about the earth, but with the earth not in its center. A circle described about the center of an elliptical orbit, with half the major axis for radius.
4. (Science: machinery) a disk or wheel so arranged upon a shaft that the center of the wheel and that of the shaft do not coincide. It is used for operating valves in steam engines, and for other purposes. The motion derived is precisely that of a crank having the same throw. Back eccentric, the eccentric that reverses or backs the valve gear and the engine. Fore eccentric, the eccentric that imparts a forward motion to the valve gear and the engine.