plumber’s smile

plumber’s smile

and working man’s smile
n. the upper part of the gluteal cleft (crack sense 1) visible above the beltline of a man, bent over at work. I came into the kitchen and was greeted by a plumber’s smile owned by some guy working under the sink. She referred to the overexposure of his rear end over his belt as the “working man’s smile.”
See also: smile