The definition of eccentric is something that is not exactly circular.(adjective)
An example of eccentric is the orbit of Mercury.
Eccentric is defined as someone or something that is different or behaves in an unconventional way.(adjective)
An example of eccentric is an adult wearing footy pajamas to a formal dinner.
See eccentric in Webster's New World College Dictionary
Origin: ME eccentrik < ML eccentricus < LL eccentros, out of the center, eccentric < Gr ekkentros < ek-, out of (see ex-) + kentron, center
See eccentric in American Heritage Dictionary 4
Origin: Middle English eccentrik, planetary orbit of which the earth is not at the center
Origin: , from Medieval Latin eccentricus, not having the same center
Origin: , from Greek ekkentros
Origin: : ek-, out of; see ecto-
Origin: + kentron, center (from kentein, to prick; see kent- in Indo-European roots).
eccentric circles, with the center of each circle marked
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