(adjective)
differing from the accepted or established style, usage, or pattern;
e.g. They often develop eccentric solutions to problems.
(adjective)
not located at the geometric center, or having an axis that is not located at the geometric center;
e.g. The awards stand was eccentric in the circular racetrack, located closer to one edge.
(adjective)
not following a strictly circular path, often following an elliptical (oval-shaped) path instead;
e.g. The planet has an eccentric orbit around the sun.
(noun)
an unconventional person who is odd/strange in manner, behavior, or views;
e.g. She became an eccentric who does as she pleases without caring what other people think.
(noun)
a mechanical device that consists of a wheel/disk that is mounted in an off-centered fashion to a rod or shaft in order to transform motion between back-and-forth and rotating;
e.g. The eccentric in the engine snapped, causing the engine to malfunction.