This is a common drink in dive bars in Massachusetts, consisting of Dr. McGillicuddy's on the rocks in a plastic cup.

This is a reference to Brockton Mass, a hardscrabble town that has a fondness for bottom shelf liquor because it is cheap and effective.
Bartender: “What’l it be?”
Dive Bar Dweller: “Give me the Brockton mouthwash.”
by LCAlum April 4, 2019
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