Green’s Dictionary of Slang

1. fortunately having escaped from something; as in well out of it.

1872		J.D. McCabe Lights & Shadows 701: [R]espectable people rarely leave the cars in this dirty thoroughfare, and are heartily glad when they are well out of it [i.e. the ‘red light’ area].
1899		J. Conrad ‘The Heart of Darkness’ in Blackwood’s Mag. Mar. 496/1: ‘Did I mention a girl? Oh, she is out of it—completely. They—the women I mean—are out of it—should be out of it. We must help them to stay in that beautiful world of their own, lest ours gets worse. Oh, she had to be out of it’.
1911		E.J. Brady Tom Pagdin Pirate 105: [of a state of imprisonment] ‘We've got to get out of this.’ ‘Yes,’ agreed Dave; I reckon the sooner we get out of it the better. It ain’t lucky’.
1915		R. Norton letter 14 Oct. in DeWolfe Howe Harvard Volunteers (1916) 101: [T]hey had no idea that the attack would be anything like so severe as it was. Those I have talked to said it was awful, and they were glad to be out of it.
1917		C. Charles letter 26 July in Rockwell American Fighters in the Foreign Legion 272: [T]hey had been under the bombardment for six days and were glad to get out of it.
1920		(ref. to 1910) F. Young (ed.) Trial of H.H. Crippen 111: Oct. 21, 1910 testimony of H.H. Crippen: I might have thought, well, if there is all this suspicion [...] perhaps until this woman is found, I had better be out of it.
1954		Wodehouse Jeeves and the Feudal Spirit 80: She is well out of it.
1965		E. Bond Saved Scene x: Yer well out a it.

2. (orig. US) excluded from one’s usual participation in something.

1880		‘’Arry’s Christmas in the Country’ Punch 25 Dec. in P. Marks (2006) 30: I was out of it, jolly clean out of it.
1900		Flynt & Walton Powers That Prey 255: I was out of it here too an’ got flat on my uppers.
1910		H. Hapgood Types from City Streets 48: He is consequently side-tracked, ‘out of it’.
1925		J.C. Lincoln The Managers 17: hiram: But there, he’s gone and past. He’s out of it. gertie: What do you mean by ‘out of it?’ hiram: Eh? Haven’t you heard? Randall Holt’s engaged.
1935		A. Christie Three Act Tragedy (1964) 106: Poor thing, she looked rather out of it.
1959		E. De Roo Young Wolves 69: She brought to mind Cliff, and he sat glumly staring, more and more out of it while she did her dance.
1967		C. Cooper Jr Farm (1968) 97: You said you want to get Out of It, and I do too.
1978		L. Kramer Faggots 81: My forty-three-year-old body won’t muscle up like that. I’m out of it.
1989		M. Amis London Fields 201: This happens, I’m out of it. I’m history. I’m a fucking dinosaur.

3. out of touch, behind the times, not au fait with current affairs and interests, unfashionable.

1883		‘’Arry on His Critics and Champions’ in Punch 14 Apr. 180/1: I’m not quite so out of it, Charlie, as this yere Jorkins might think.
1885		Bulletin (Sydney) 21 Feb. 6/3: But the treaty is popular in the Island, and the Sydney dalies [sic], are, as usual, ‘out of it.’.
1910		Bulletin (Sydney) 21 July 13/1: ‘Is it where the squatters squat their sheep, / And large and easy incomes reap [...]?’ / ‘Clean out of it, me che-ild.’.
1936		W.R. Burnett King Cole 261: He would be nothing to Jean anymore but a middle-aged man, quite out of it so far as Jean and her set were concerned.
1945		W.R. Burnett Tomorrow’s Another Day 17: [M]ost men his age were married and had kids. A single man had very little in common with the head of a family; he was out of it, that’s all.
1954		Post Standard (Syracuse, NY) 16/1: Some of the expressions are ‘such rot,’ ‘real cool,’ ‘what are you, a bargain?’, ‘he’s out of it,’ ‘out to lunch,’ ‘who needs it?’, ‘there’s a fungus among us.’.
1969		Cressey & Ward Delinquency, Crime, and Social Process 808: A ‘lame dude’ does not ‘know what’s happening.’ He is ‘out of it’.
1977		C. McFadden Serial 68: Paranoia [...] was Harvey’s bag, but Kate was starting to feel a little out of it.
1989		H. Rawson Dict. of Invective (1991) 278: It is not good to be out, e.g. [...] out of it.

4. dead.

1915		T. Burke Nights in Town 175: ‘Out of it? How?’ ‘Done herself in.’ ‘What?’ ‘Cocaine. Overdose.’.
1916		T. Burke Limehouse Nights 74: Now that Kang Foo Ah is out of it.
1969		C. Sellers Where Have All the Soldiers Gone 42: ‘Simpson’s out of it; we’ll pick him up on the way back’.