Describes anything cool or new. Chill. It can also describe an attractive female. Not to be confused with the slang term for a popular alcoholicbeverage. The term originated as Jamaican slang.
It refers to Darren Criss, who plays a gay man on television and when interviewing in real life he ALWAYS makes a point to say that he is straight and point out his heterosexuality. therefore Crissing is an insistent declaration of one's heterosexuality