Green’s Dictionary of Slang

1. to die.

1908		B. Fisher A. Mutt in Blackbeard Compilation (1977) 155: A lady just fell off the Howard Street wharf and is about to kick in.
1912		D. Lowrie My Life in Prison 247: He just hangs there swingin’ until his heart stops beatin’ and the croakers announce that he has kicked in.
1918		L.N. Smith Lingo of No Man’s Land 40: GONE WEST An expression for death; likewise, the slang ‘kicked-in.’ These terms together with the phrase, ‘Pushing up the daisies’ are the soldiers’ common terms for the fate that overtakes comrades and may momentarily overtake themselves.
1926		J. Tully Jarnegan (1928) 243: Daisy Carol’s aunt kicked in.
1934		‘Maxwell Grant’ ‘Murder Marsh’ in Shadow Oct. 🌐 Bill was dead; Harry kicked in just after you fellows left.

2. to give up, to abandon.

1911		G. Bronson-Howard Enemy to Society 293: She thinks he kicked in th’ front fer her sake.
1929		A.J. Barr Let Tomorrow Come 159: Kick in the rag, I ain’t goin’ in any more.
1936		R.L. Bellem ‘Falling Star’ in Spicy Detective Sept. 🌐 He spoke to the Filipino chicken again. ‘I’ll put you under the daisies if you don’t kick in with that ring, you damned Gugu slut!’.
1970		‘Red’ Rudensky Gonif 5: You might as well kick-in out here as well as in the city.
1975		‘P.B. Yuill’ Hazell and the Three-card Trick (1977) 44: So that was how I kicked in my steady wages and got my first client.