Green’s Dictionary of Slang

to pretend, to pose as (if).

1888		‘Rolf Boldrewood’ Robbery Under Arms (1922) 152: We made out that there was no great chance of our being run in at the old place.
1906		O.W. Hanley ‘Dialect Words From Southern Indiana’ in DN III:ii 121: make out, v. [...] (2) To pretend, feign. ‘He’s makin’ out like they want to go.’.
1912		R.W. Brown ‘Word-List From Western Indiana’ in DN III:viii 582: make out like, v. To pretend. ‘He made out like he was going to town.’.
1947		B. Schulberg Harder They Fall (1971) 116: Make out like you can’t get an opponent for him [...] because nobody around there’s got the guts.
1948		J. Archibald ‘Klump a la Carte’ Popular Det. July 🌐 Make out we never drunk no beer together t’night.
1955		E. Hunter Blackboard Jungle 331: He makes out like he’s a big shot.
1960		J.D. Macdonald Slam the Big Door (1961) 95: They make out like they’re just old cracker boys, but they’re made of money.
1971		Ed Bullins ‘Dandy’ in King Black Short Story Anthol. (1972) 75: Old Dandy’s makin’ out like a madman.
1982		J. Sullivan ‘Ashes to Ashes’ Only Fools and Horses [TV script] Well he wasn’t as soppy as they made out then was he?