The origins of the word oxymoron:
oxymoron
1657, from Gk. oxymoron, noun use of neut. of oxymoros (adj.) “pointedly foolish,” from oxys “sharp” (see acrid) + moros “stupid.” Rhetorical figure by which contradictory terms are conjoined so as to give point to the statement or expression; the word itself is an illustration of the thing. Now often used loosely to mean “contradiction in terms.”
Online Etymology Dictionary, © 2001 Douglas Harper
I guess reading is a bit tedious, so compare it with watching this youtube video.
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Note: Was in …