Green’s Dictionary of Slang

sentimental, mawkish.

c.1930		(ref. to late 19C) N. Kimball Amer. Madam (1981) 131: Zig liked smaltzy German tunes about black forests and trolls.
1939		A. Kober Pardon Me for Pointing 165: A schmoltzy old guy like Lionel Barrymore.
1939		Detroit Free Press (MI) 17 Sept. 8/2: ‘You schmal’zy old long-hair, you!’.
1946		Charleston (WV) Daily Mail 2 Sept. 6/5: Me schmaltzy gabber couldn’t red a Chicago piano rap, so the D.A. conks me with a whole mag.
1964		J. Gelber On Ice 228: The faggot was a dabbler of paints, a schmaltzy colorist.
1978		F. Norman Dead Butler Caper 18: She was getting schmaltzy and I thought it was time to intervene.
1986		L. Heinemann Paco’s Story (1987) 105: There are thousands of these restaurants, James, each with its own schmaltzy gimmick.
1989		R.G. Barrett Boys from Binjiwunyawunya 295: Every schmaltzy record on the top forty that Norton despised.
1992		K. Lette Llama Parlour 210: I had never felt so, well . . . Schmaltzy as it was, the only word was — happy.
2004		L. Redhead Peepshow [ebook] A schmaltzy song by some American boy band was playing.
2009		R. Milward Ten Storey Love Song 173: A long-winded bout of stroking one another, which seems a bit schmaltzy.
2014		Ruderman & Laker Busted 76: When she showed me her profile, I blurted, ‘Oh, Barbara, that’s soooo schmaltzy. You gotta change that’.