When you urinate, after sexual intercourse or masturbation in which you have achieved ejaculation, Jiss is the chunky-ish white semen left over that gets shot out while said urination is taking place.
We've all seen a jiss I'm sure. Also known as the gusher, the squirter, the juicer. This term is used for when a woman, gets butt nekkid squats down and ejaculates a hugely long triumphant ribbon of clear pisslike and jizzlike liquid during orgasm. However... its not jizz... its not piss.... ITS JISS