Ad nauseam is defined as something that happens over and over, or that goes on for so long that everyone is sick of it.(adverb)
An example of ad nauseam is the story that your professor repeats at the beginning of every single class.
See ad nauseam in Webster's New World College Dictionary
Origin: L, to nausea
See ad nauseam in American Heritage Dictionary 4
Origin: Latin ad, to
Origin: + nauseam
Origin: , accusative of nausea, sickness.
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