Green’s Dictionary of Slang

to defend, to champion.

1844		‘Jonathan Slick’ High Life in N.Y. I 214: I wanted to stick up for Sam, but I’ll be darn’d if I could see how to.
1858		F.W. Farrar Eric II 249: You know how often he tries to stick up for Rose.
1862		Thackeray Adventures of Philip (1899) 602: Ringwood stuck up for you and for your poor governor.
1873		Sl. Dict.
1882		Daily Tel. 6 Oct. 2: He’d do it more, only mother rounds on him about it, and sticks up for us.
1894		G. du Maurier Trilby 195: Why didn’t you stick up for her?
1915		Bulletin (Sydney) 5 Aug. 47/1: [O]ne night, when I ’ad a few in, a couple of Johns got onto a cobber of mine, an’ I stuck fer ’im and stoushed one of the cops.
1923		H.C. Witwer Fighting Blood 77: I’m glad to say, though, that Mrs. Willcox stuck up for us.
1936		‘Banjo’ Paterson Shearer’s Colt 114: I stick up for the Irish when I’m here, but I stick up for the Australians when I’m at Home.
1940		B. Appel People Talk (1972) 46: Stickin’ up for the Jews, he must be a Jew!
1950		‘Hal Ellson’ Tomboy (1952) 12: One minute [...] you’re going to slap him down and the next minute you’re sticking up for him.
1965		E. Bond Saved Scene x: It’s your place t’ stick up for me, love. I went through all that trouble for you!
1976		P. Theroux Family Arsenal 140: I ain’t sticking up for you this time. It’s your look-out.
1981		S. Berkoff Decadence in Decadence and Other Plays (1985) 29: Stick up for us – have a little pluck.
1998		G. Burn Happy Like Murderers 60: She’d stuck up for her a few times in front of Fred.