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) vi., to collapse in laughter, vtr., to reduce someone to 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.
1953		‘John Monahan’ [W.R. Burnett] Big Stan 62: ‘It [i.e. a funny line] breaks me up,’ said Katie, shaking with laughter.
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.