Green’s Dictionary of Slang

sweetheart n.

[ext. of SE, often ironic]

1. as a term of address; no affection is implied.

[US](con. 1900s) S. Lewis Elmer Gantry 48: ‘I’ll explain how I feel.’ ‘Oh no, you won’t, sweetheart!’.
[US]E. O’Brien One Way Ticket 119: ‘Hello, sweetheart.’ Mac did not answer.
[US]R. Martin ‘Tea Party Frame-Up’ Mammoth Detective May 🌐 All right, sweetheart, we’re all through fooling.
[US]R. Chandler Long Good-Bye 295: ‘You got crossed up, sweetheart,’ Ohls told him carefully.
[UK]G.W. Target Teachers (1962) 118: Just so long as we understand each other, sweetheart.
[US]J. Webb Fields of Fire (1980) 89: Don’t be sorry, sweetheart, just answer my goddam question.
[US](con. 1967) E. Spencer Welcome to Vietnam (1989) 110: This is my time now, and you’re with me, sweetheart.
[UK]J. Mowry Six Out Seven (1994) 191: Yeah, sweetheart, just one more sorry motherfucka in this great big sorry-ass motherfucker.
[UK]M. Coles Bible in Cockney 13: The snake replied [...] ‘God ain’t gonna kill you, sweetheart.’.

2. a person; usu. used in a derog. sense.

[US]Hostetter & Beesley It’s a Racket! 240: sweetheart—Anyone you particularly dislike.
[US]C. Odets Golden Boy II iv: You’re a real sweetheart ...
[US]H. Hunt East of Farewell 49: He’s a sweetheart [...] So he’s got psychic powers now.
[US]R. Chandler Long Good-Bye 67: You didn’t spend three days in the freezer just because you’re a sweetheart. You got paid off.
[US]W. Diehl Hooligans (2003) 42: He favours a nine-millimetre Luger [...] A real sweetheart. He’s also a muscle freak.
[US]L. Stringer Grand Central Winter (1999) 69: ‘We’ve got a sweetheart of a judge out there,’ he beamed.

3. anything considered good.

[US]G. Milburn ‘Convicts’ Jargon’ in AS VI:6 441: sweetheart, n. Anything that is swell.
[US]Goldin et al. DAUL 216/2: Sweetheart. 1. One easily victimized; a place easily and profitably robbed. ‘That jug (bank) is a sweetheart for a pete-job (safe-robbery).’ 2. An extremely desirable person or thing.
[US]R. Daley To Kill a Cop 200: ‘It’s a sweetheart, that gun’.

4. (US Und.) a stolen automobile in good condition.

[US]Monteleone Criminal Sl. (rev. edn).

SE in slang uses

In compounds

sweetheart man (n.)

(US black) a man who is not married to his lover.

[US]Davis & Dollard Children of Bondage 258: Sara Mae’s mother [...] was not married to Sara Mae’s father. ‘He was a sweetheart man,’ with whom she lived for only three weeks.