Green’s Dictionary of Slang

1. (US) an inferior or cowardly prize-fighter; also fig. use.

1925		Chicago Trib. 19 Sept. 2/4: ‘Sure, I’ll fight when a guy he gets off base. I ain’t got round heels.’ ‘You bet Terry’s not got round heels,’ seconded Mr Lake.
1934		G. & S. Lorimer Stag Line 81: ‘Knock that smile offa him, Bat!’ ‘Smiling Sam, yah, round-heel!’ ‘What’s a round-heel?’ I asked Davy. ‘Round-heel’s a pushover.’.
1947		B. Schulberg Harder They Fall (1971) 12: Old Joe Roundheels, who couldn’t lick my grandfather.
1951		Green & Laurie Show Biz from Vaude to Video 571: Round heels – a pushover.
1985		F. Deford in Sports Illus. June 🌐 A prospect is brought along against hand-picked roundheels on Sunday afternoon TV.

2. (also little Miss Roundheels, little roundheels, Miss Roundheels, roundheel) a promiscuous woman (cf. light heels n.; short heels n.).

1921		Broadway Brevities Dec 20: Who's Jessie Reid’s shoemaker? Understanding is that Jessie wears round heels.
1928		Amer. Mercury 13 178: It was Adam Kapechik who found Round Heels lying by the roadside in her shoes, stockings and knickers and with her torn dress.
1935		A.J. Pollock Und. Speaks n.p.: Round heels, an immoral woman easily approached.
1939		D. Maurer ‘Prostitutes and Criminal Argots’ in Lang. Und. (1981) 117/1: bladder. An unattractive prostitute. Also beetle, blister, boat-and-oar, body-snatcher, broken car, bum curtain, cat, curb-sailor, dog, doll, hay-bag, nanny, nautch girl, oak door, pisga rib steak, round-heels, sloop-of-war, swinging door, tabby, tart, tomato, each expressing varying degrees of unattractiveness.
1943		R. Chandler Lady in the Lake (1952) 39: You’d think if I had to jump off the dock I’d [...] pick me a change in types at least. But little roundheels over there ain’t even that.
1951		(con. 1920) S. Longstreet Pedlocks (1971) 273: Come on, roundheels, let’s go back upstairs.
1951		S. Lewis World So Wide 239: I’m not a round-heel like Livy.
1955		B. Moore Judith Hearne 57: And she’s a scared kid, little roundheels, couldn’t have much religion.
1959		R.C. Ruark Poor No More 211: Little Miss Round Heels in person. Don’t pay her no money. Buy her a meal and shove her into the sack.
1962		J. Quirk No Red Ribbons (1968) 156: There were four young men and four round-heels from town.
1974		J. Lahr Hot to Trot 16: Does she really do it? [...] Round heels, huh?
1975		T. Berger Sneaky People 243: Mary was no Miss Roundheels: Buddy had had virtually to rape her the first time.
[1986		R. Campbell In La-La Land We Trust (1999) 65: She was no pushover. Her heels weren’t round].
1989		H. Rawson Dict. of Invective (1991) 331: round-heels. One who is easily pushed over, as an incompetent pugilist or, the more usual context, a compliant woman.
1990		(con. early 1950s) J. Ellroy L.A. Confidential 170: A string of patriotic roundheels on his bond tour.
2001		cwnews ‘Events’ in Eye on CameraWare III Apr. 🌐 Just to know the joes, I brought up a couple of male videos. A couple of roundheels and a slackjaw or two, but all in all they looked like pretty good eggs.
2012		T. McCauley ‘Redemption’ in ThugLit Dec. [ebook] Once a round heel, always a roundheel‘’.

3. (US gay/prison) a victimized young inmate, forced into homosexuality.

1972

B. Rodgers Queens’ Vernacular 161: sexually oppressed, constantly raped victim; usually straight [...] roundheels.