Green’s Dictionary of Slang

1. (orig. US) armed.

1852		C.L. Canfield Diary of a Forty-Niner (1906) 192: I followed suit with the shotgun and pistol. We both stood in the door and when they rode up they saw we were heeled.
1867		Terr. Enterprise 15 Mar. 3/1: Let those in the habit of going ‘heeled’ take heed [DA].
1873		Daily Missouri Democrat 15 March in Miller & Snell Why the West was Wild 207: When the Texan shot Wild Bill, he asked the crowd in the bar-room if any gentleman had any desire to ‘mix in’; if so, he would wait until he was ‘heeled’, and take great pleasure in killing him.
1877		E.L. Wheeler Deadwood Dick in Beadle’s Half Dime Library I:1 88/2: Are you well-heeled?
1887		F. Francis Jr Saddle and Mocassin 62: A couple of leather-overalled cowboys, ostentatiously ‘heeled’.
1899		C.J.C. Hyne Adventures of Captain Kettle 186: Don’t blame you for coming ‘heeled,’ boss. Guess a gun sometimes chips in handy round here.
1900		Bulletin (Sydney) 15 Sept. 10/3: It was his own fault for not going ‘heeled,’ as these bush-whackers call it. We all carry guns when ashore.
1927		H. Yenne ‘Prison Lingo’ in AS II:6 280: One bird is ‘heeled’ (armed) with a ‘shiv’ (knife), a ‘smokewagon’ (gun), and the other with a ‘gat’ (revolver) and a ‘jerry’ (a small 38-calibre pistol carried up the sleeve).
1931		(con. 1913) C.W. Willemse Behind The Green Lights 291: Anna Britt [...] hurried over to Philadelphia and returned packing several guns in a satchel to make sure the boys were well heeled.
1940		S. Longstreet Decade 317: He’s heeled. So watch out for his roscoe.
1955		E. Hunter ‘See Him Die’ in Jungle Kids (1967) 102: Django was always heeled [...] either with brass knucks or a switch knife or a razor or a zip gun.
1962		Ragen & Finston World’s Toughest Prison 803: heeled – Armed.
1968		J. Alard He who Shoots Last 58: We’re all healed [sic].
1972		E. Grogan Ringolevio 45: Always try to be heeled with some sort of weapon.
1993		G.P. Pelecanos Nick’s Trip 235: Boyle said, ‘I’m already heeled.’ He pulled back the collar of his Harris tweed jacket, showing me the Python. Then he reached into the bag and retrieved a five-shot .38 Special.
2000		(con. 1940s–60s) Décharné Straight from the Fridge Dad.
2001		D. Looser Boobslang [U. Canterbury D.Phil. thesis] 86/1: heel v. to arm oneself: ‘You going to go on him? Watch out, he’s heeled.

2. (orig. US) prepared.

1873		J.H. Beadle Undevel. West 190: As it was my first visit to Washington, I was but poorly ‘heeled’ for the work.
1880		‘Mark Twain’ Tramp Abroad Ch. xxxii: Her stripling brought an armful of aged sheet-music from their room — for this bride went ‘heeled’ as you might say.
1892		DN I 230: Kentucky Words [...] to be heeled = to be prepared for an undertaking. (So to be well heeled, Massachusetts.) .

3. in possession of (other than money or guns).

1878		F.H. Hart Sazerac Lying Club 45: I always used to go heeled with bread and ’lasses...for fear of accidents.
1906		(con. 1917–18) S. Ford Shorty McCabe 192: He means to go back heeled with the permit from me, with the little matter of the two million ready all cinched.
1928		C. MacArthur War Bugs 200: German prisoners invariably were well heeled with such items as salmon and hardtack.

4. busy.

1915		S. Ford Torchy, Private Sec. 207: As I was well heeled with work of my own I didn’t even glance up.
1932		Arizona Dly Star (Tuscon, AZ) 23 July 8/3: ‘I’m out here in California trying to line up a couple more jobs [...] I can’t kep the mob heeled on empty beer kegs’.

5. in possession of money.

1936

(con. 1895) T. O’Reilly Tiger of the Legion 86: ‘How’re ye heeled, Tiger?’ I dived into my pocket, and produced my total wealth—two notes and some nickel.

6. intoxicated by or in possession of drugs.

1950		Goldin et al. DAUL 94/1: Heeled. [...] 3. (Rare) Intoxicated or under the influence of drugs.
1969		R.R. Lingeman Drugs from A to Z (1970).
1971		E.E. Landy Underground Dict. (1972).