A spinster over the age of 70 with no hair growing below her navel with a leathery crustyoverused snatch.
Gloria was a great grandmother during the week but on the weekends her and her friends were a bunch of wild Crustangs. Crustang Sally you better slow that Crustang down. Bob was in for the ride of his life when he found out she was a Crustang.
A trip to a grocery store, convenience store, or gas station for the sole purpose of buying an excessive amount of junk food and sugary drinks, usually with friends. A chud run often happens late at night and ends with everyone involved hating themselves afterwards.