To renege is to abandon something or go back on something you had promised.(verb)
When you promise to take your child to the circus and then you change your mind and don't go to the circus, this is an example of a situation where you renege on a promise.
See renege in Webster's New World College Dictionary
Origin: ML renegare: see renegade
See renege in American Heritage Dictionary 4
verb re·neged, re·neg·ing, re·neges verb, intransitive
Origin: Medieval Latin renegāre, to deny; see renegade.
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