The mysterious liquid or goo commonly found on the pavements and in the alleys of chinatowns all over the world that give chinatowns their distinctive smell.
This material is normally organic and made from the rotting juices of animal carcasses, urine of unknown origin, pavement-pureed fruits, produce and meats, and the phlegm of a pack-a-day smoker. The proportions will vary. Once those ingredients are well-mixed by foot traffic, a hot and humid summer day cooks it or ferments it.
Chinatown jizz gives rise to chinatown stench and is closely related to chinatown cheese.
Person A: What's the smell?
Person B: Dude, that's chinatown jizz. You stepped on it.
Person A: What? I stepped on jizz?
Person B: At least it didn't hit you in the face.