Vomiting; throwing up; hurling; puking etc. etc.
More specifically: Throwing up in someone's
car.
Background: After eating McDonald's, Cliff threw up all over Max's
car, therefore throwing up in someone's
car became "cliffing" and then it became a general term for vomiting.
After eating some suspect
curry and smoking too much pot,
Zak ended up cliffing all over the back of our
van.