Definitions by W.W. Gnuttsack

Winter walnut 

The tightly bound, ridged and rippled condition of the scrotum that happens during the colder months of the year, paying soft homage to the outer shell of a walnut.

Dude, turn off the AC. It’s the middle of July and I’m rocking a winter walnut over here!

Winter walnut by W.W. Gnuttsack June 27, 2019