An armpit is defined as the body part underneath the area where the arm meets the shoulder.(noun)
The area on the body where people apply deodorant is an example of an armpit.
The definition of an armpit can refer to a bad, gross or unpleasant place.(noun)
An example of an armpit is the dirty section of a city known for its high crime rates.
See armpit in Webster's New World College Dictionary
See armpit in American Heritage Dictionary 4
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