Green’s Dictionary of Slang

1. (US) to make someone very upset, to make someone ill with tension, to cause someone to cry.

1789		Thrale Thraliana ii 1 Apr. 739: Mrs Byron is now old & infirm, & apparently in her last Stage of Existence—Lady Wilmot's Death last Year broke her up, & She cd never recover to be what She was before .
1883		Bismarck (ND) Trib. 26 Jan. 8/1: The minister preached how vulgar it was to use slang [...] Just the minute I caught on to his racket, it broke me all up.
1895		E. Townsend Chimmie Fadden Explains 7: Say, honest, dat broke me all up.
1902		Bulletin (Sydney) 9 Aug. 17/2: This bard, who sits a-watching Nell, / With fingers white and slim, / Owns up that, as she breaks each shell, / She also ‘breaks up’ him; / And could devoutly drop upon / Submissive, bended knees.
1907		Gem 16 Mar. 5: It broke my governor up.
1917		Wodehouse ‘Wilton’s Holiday’ Man with Two Left Feet 42: He told me the whole thing so simply and frankly that it broke me all up.
1922		E. Raymond Tell England (1965) 297: The boyish words broke me up. My brows contracted in pain. My eyes burned.
1937		P. Cheyney Dames Don’t Care (1960) 126: I said it was pretty tough for me being sick to think she was running around with a guy who had swindled me. Well, that broke her up. I reckon she was sorry.
1956		B. Behan Quare Fellow (1960) Act II: It’ll break that young screw up.
1960		Mad mag. June 49: Man, I broke up at this crudest bird who wailed like some Zen Buddhist.
1960		E. De Roo Big Rumble 109: Next time I’ll break you both up, you fight in my store.
1977		in K. Gilbert Living Black 142: Well, it broke me up.
1978		R. Charles Brother Ray 54: By forcing me to break up, Ma Beck might have kept me from breaking down. Once the tears started to flow [etc].
1988		McGill Dict. of Kiwi Sl. 21/1: break up demonstrate great amusement or, contrarily, upset.
1999		N. Cohn Yes We have No 209: My ex-girlfriend has another man now, and that breaks me up.
2003		McGill Reed Dict. of N.Z. Sl. [as cit. 1988].

2. (orig. US, also break it up) to disconcert or break someone’s flow, e.g. to cause someone to laugh or applaud heartily; to applaud heartily.

1881		‘Bill Nye’ Bill Nye and Boomerang 96: When I read this little thing [...] it broke me all up.
1926		C. Ryan ‘From “Quoz” to “Razzberries”’ in AS II:2 91: It is reported that a judge once used it inadvertently, and well nigh broke up the court.
1944		Cab Calloway New Hepsters Dict. in Calloway (1976) 253: break it up (v.): to win applause, to stop the show.
1952		W.R. Burnett Little Men, Big World 39: It must be something pretty funny to break up a tired broad like Lola.
1956		Billie Holiday Lady Sings the Blues (1975) 40: Then the house broke up. There’s nothing like an audience at the Apollo.
1964		H. Selby Jr Last Exit to Brooklyn 88: Roberta really broke us up.
1978		S. King Stand (1990) 151: This never failed to break Poke up. He brayed laughter.
1982		S. King Different Seasons (1995) 196: On the TV, Buddy Hackett had just broken everybody up.
2020		A. Trebek The Answer Is 67: [O]n the air he was the perfect announcer, rock solid. So we delighted in trying to break him up.

3. (US) to act hysterically, to act irrationally; in weak use, to cry (see cite 1996).

1900		Bulletin (Sydney) 6 Jan. 12/3: Juvenile Melbourne was ‘breaking up,’ and showing off for many weary days before Plum-puddingness.
1941		K. Tennant Battlers 310: Poor old bugger’s breaking up fast.
1965		T. Wolfe Kandy-Kolored Tangerine-Flake Streamline Baby (1966) 24: I’m breaking up, and I don’t even know what’s happening to me.
1992		Bentley & Corbett Prison Sl. 93: Nut Up To completely lose control of oneself. […] (Archaic: blow one’s roof, break up).
1996		W.D. Myers Slam! 83: Moms broke out into crying again [...] It made me feel bad to see Moms break up.

4. (also break) to collapse in laughter.

1895		‘Mark Twain’ in North Amer. Rev. Jan. 61: Well, humour is the great thing, the saving thing, [...] so, when M. Bourget said that bright thing about our grandfathers, I broke all up.
1939		Goodman & Kolodin Kingdom of Swing 92: [W]e had to stand up, and the band nearly broke it up, it laughed so much.
1960		Mad mag. Sept. 46: All the hipsters always break up when I make the scene. They keep laughing at me.
1974		(con. 1940s) E. Thompson Tattoo (1977) He knew Glenn and Bucky were breaking up.
1978		R. Price Ladies’ Man (1985) 45: Jerry and Maurice broke up. Al basked in their laughter.
1989		(con. 1982–6) T. Williams Cocaine Kids (1990) 100: Everybody in the joint broke. It was funny as shit.
1991		B. McCarthy Vice Cop 160: ‘Let’s show a little respect for our new partner.’ ‘Respect this,’ Tony answered, suddenly grabbing at his crotch. This time, even Flash Gordon broke up.
2003		McGill Reed Dict. of N.Z. Sl.