Green’s Dictionary of Slang

to vanish, to disappear; the implication is of stopping causing trouble.

1902		C.L. Cullen More Ex-Tank Tales 40: If I made any effort whatsoever to get lost [...] he’d joggle down to police headquarters and send out a general alarm for me.
1912		Derby Dly Teleg. 24 Sept. 4/5: ‘What would you do if you were in my shoes?’ ‘I’d get lost, I’m afraid’.
1952		(con. 1948) G. Mandel Flee the Angry Strangers 134: ‘Why don’t you get lost?’ Buster growled.
1955		B. Schulberg On the Waterfront (1964) 208: I’d be willing to make a nice contribution if this Barry would only get lost.
1963		A.S. Fleischman Venetian Blonde (2006) 148: I told you to get lost.
1976		P. Theroux Family Arsenal 63: If a carpenter joins and says he wants to be a hit-man, we tell him to get lost.
1984		‘Derek Raymond’ He Died with His Eyes Open 73: Paying me to get lost, are you?
1999		T. Dorsey Florida Roadkill 91: Serge told Sharon to get lost.
2001		A. Sillitoe Birthday 114: You should have heard the language when the woman across from me told her swain to get lost as well.