Found 2 items, similar to shack up.
English → English (WordNet) Definition: shack up shack up v : room or live together; usually said of people who are not married and live together as a couple [syn: cohabit]
English → English (gcide) Definition: Shack up Shack up \Shack" up`\, v. i. 1. to live together in a sexual relationship, without being legally married. [Slang, U. S.] [PJC] 2. to live in a cabin, shack, or other crude dwelling. [Slang, U. S.] [PJC]