Green’s Dictionary of Slang

1. (also big-shit-shot) an important person or one who claims to be so.

1934		H. Miller (1963) Tropic of Cancer 125: They’d make him out to be a big shit if they could.
1965		C. Himes Cotton Comes to Harlem (1967) 138: Goodbye, big shit.
1971		R.D. Pharr S.R.O. (1998) 321: Ginsbrug and Epstein don’t pay off them Welfare bigshits like they oughta.
1976		P. Theroux Family Arsenal 190: Then you’ll be the big shits.
1978		R. De Christoforo Grease 138: So, Mr. Sonny La Tierri, Mr. Big-Shit-Shot.
1989		(con. 1982–6) T. Williams Cocaine Kids (1990) 101: You know, Chillie wants to be big shit all the time now.

2. serious business.

2000

W. Shaw Westsiders 31: My brother was on some big shit. Crips. Real, real shit.

3. substantial profits.

2020

Woods & Soderburg I Got a Monster 127: ‘He’s got half a key here, we can get big shit.’.