Green’s Dictionary of Slang

1. (US) a murder.

1939

R. Chandler ‘Trouble Is My Business’ in Spanish Blood (1946) 209: He’s going to be awfully damn sorry about that kill.

2. (UK Und.) in fig., use, the actual moment of bringing a confidence trick to a climax.

1935		S. Horler London’s Und. 45: The greater section of the Underworld emerges from bolt-holes and luxury flats alike, intent on the evening’s ‘kill’.
1941		V. Davis Phenomena in Crime 83: A ‘kill’ (perpetrating the crime).

3. (US black) an impressive person or thing [abbr. of killer n. (2)].

1942		in Yank 5 Aug. 9: She’s a kill [HDAS].
1947		S.C. Adams Jr. interviewee q. in Adams Thesis in Gordon & Nemerov Lost Delta Found (2005) 279: I like to see the cowboys, and them colored peoples that they show from Chicago. They's really a kill .

4. a major coup, esp. in criminal terms.

1954		E. Hunter ‘The Beatings’ in Jungle Kids (1967) 134: I’d made a big kill. Six bits from some society guy and his broad.
1981		J. Ellroy Brown’s Requiem 76: We were rogue cops, out for the big kill.
1997		L. Davies Candy 203: They’d often gone for the big cash kill and done doubles together.

5. see killing n.