A social trend dating back to the 1940's or so amongst coloured people (mixed race) in the Cape Flats townships of Cape Town, South Africa, where the front 4 incisors are removed from one's mouth, thereby facilitating oral sex. This is often rued by the older generation, who regret their desire to give better head when they hit their 40's.
-Yo, check out the passion gap on her. I bet's she can like to give lankkiff head.
-A local supermarket chain has insisted on all employees having dental work done, so as not to scare customers with their "passion gaps."