The definition of a dumbbell is a device with a short bar between two weights, used for exercise or building muscles, or is slang for a dumb person.(noun)
An example of a dumbbell is a set of two five pound weights used for exercise at home.
See dumbbell in Webster's New World College Dictionary
Origin: cf. dumb, senseSlang a stupid person
Origin: dumb + bell: from orig. shape
See dumbbell in American Heritage Dictionary 4
Origin: From an apparatus similar to that used in ringing a church bell, but without the bell, used for practice or physical exercise.
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