The definition of facetious is a joke made about something serious.(adjective)
An example of facetious is someone saying that people whose homes have burned down don't have to worry about whether the housekeeper did a good job.
See facetious in Webster's New World College Dictionary
Origin: Fr facétieux < L facetia: see facetiae & -ous
See facetious in American Heritage Dictionary 4
Origin: French facétieux
Origin: , from facétie, jest
Origin: , from Latin facētia
Origin: , from facētus, witty.
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