First called a "BIKE JOCKEY STRAP" in the 1890s,it was sold to bicyclists to prevent NUT ACHES while riding a bike on bumpy, unpaved roads. BIKE became a brand name and there famous and popular garment was known by most as a JOCKEY-STRAP until about the 1970s when its started to be known as just a JOCK.
Jocks (or Athletic Supporters) were required equipment for all 7th. through 12 grade boys during P.E. class at most all of the nation's schools until about 1985 a trend toward loose nuts (the boxer rebellion) may have been the downfall of the JOCK-
strap in America.
A Chocolate Chin Strap is like a Blumpkin for a girl. The male applies the mouth to the females vagina. Once there he starts eating her out while, the female is taking a shit. Once this action starts her shit then leaves a tiny chin strap appearance on your face.
"Dude whats that brown stuff on your face?" tom says.
"Not much man just my Chocolate Chin Strap, from my girlfriend!" john says.
"Damn that bitch is sick and so are you!" tom says.