When a male grabs his crotch area to slightly adjust the family jewls, or to scratch them.
At my job we sell automobiles. Sometimes when it's slow we all just joke around and if somebody grabs their crotch you have to call them out on it and say hammer check.

Sharif was standing in front of me telling a story and all of the sudden he does an aggressive hammer check.

Yo sharif HAMMER CHECK
by GSXR-600 May 27, 2017
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