Green’s Dictionary of Slang

1. a chat, a long and intimate conversation.

1908		Sporting Times 9 May 10/2: Let’s have a quiet little schmooze.
1939		Reader’s Digest May 106/2: Because of schmooze, the garment district is the most hypersensitive city of 200,000 in the world. . When a dress manufacturer steals a new style at 11:15 a.m., practically everybody knows about it by one o'clock.
1956		Billie Holiday Lady Sings the Blues (1973) 156: [Lena Horne] insisted on taking me out with her and bought me lunch, and we had a wonderful schmooze about the old days in Hollywood.
1997		L. Davies Candy 187: I was having visions of a new dealer, a step up, a BMW schmooze with the uncut rocks.
2000		Guardian Editor 4 Feb. 18: You’ve no idea whether you’re going to get prepared schmooze.
2023		(con. 1962) J. Ellroy Enchanters 10: Swinger joints. Schmooze pits. Stewardess crash pads. Fag cribs and bachelorette dumps for kept women.

2. flattering, persuasive talk, e.g. as used in salesmanship.

1914		Sun (NY) 10 May 8/2: The Two Spot, or Deuce, is the lowest card in the deck [...] and when used in the Selling Game means ‘schmoos’.
1937		A. Kober Having Wonderful Time (1975) [play script] 159: I don’t hand out a line of schmoos — not even in business.
1998		L. Stringer Grand Central Winter (1999) 88: Some gravel-voiced coot [...] who right off the bat starts drooling schmooze into my ear, carrying on about what a big fan of Street News he is.

3. inconsequential words.

1929		S. Ornitz Haunch Paunch and Jowl 261: Don’t dare use legal phraseology [...] you amateur lawyers love legal shmooserie ... avoid it like the plague ... always have your affidavits in your witnesses’ own language ... slang ... filth ... everything.
1937		R. Westerby Wide Boys Never Work (1938) 199: Down in Fleet Street, the Presses roar. Ten million sheets of schmooge, pouring from the machines like vomit.
1980		L. Bangs in Psychotic Reactions (1988) 296: The blues, the schmooz, same old three-chord bullshit.