The culprit is defined as the person who is responsible for something, or is the thing that is causing a bad outcome.
(noun)See culprit in Webster's New World College Dictionary
noun
Origin: < Anglo-Fr cul. prit, contr. for phr. culpable, prit (a averer nostre bille), lit., guilty, ready (to prove our case): words used by prosecutor in opening case < culpable (see culpable) + prit, for OFr prest < LL praestus, ready
See culprit in American Heritage Dictionary 4
cul·prit
nounOrigin: Probably from cul. prit, abbreviation for Anglo-Norman *culpable: prit d'averrer nostre bille, guilty: (I am) ready to aver our indictment : culpable, guilty (from Latin culpābilis; see culpable ) + *prit, ready (variant of prest, from Latin praestō; see presto ).
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