live together vs shack up

live together and shack up both are verbs.

Word	Noun	Adjective	Verb	Adverb
live together	No	No	Yes	No
shack up	No	No	Yes	No

As verbs, live together and shack up are synonyms defined as:

live together and shack up: share living quarters; usually said of people who are not married and live together as a couple

Other synonyms of live together include cohabit.

live together (verb)	shack up (verb)
share living quarters; usually said of people who are not married and live together as a couple	share living quarters; usually said of people who are not married and live together as a couple