Green’s Dictionary of Slang

1. the Recorder of London [pun on SE recorder, a flute-like instrument].

c.1698		B.E. Dict. Canting Crew n.p.: Flute, the Recorder of London, or of any other Town.
1725		New Canting Dict. [as cit. c.1698].
1737, 1759, 1760, 1776		Bailey Universal Etym. Eng. Dict. [as cit. c.1698].
1785, 1788, 1796		Grose Classical Dict. of the Vulgar Tongue.
1809		G. Andrewes Dict. Sl. and Cant.
1811		Lex. Balatronicum.
1835		G. Kent Modern Flash Dict. n.p.: Flute, the recorder of any town.
1848		Flash Dict. in Sinks of London Laid Open.
1859		Matsell Vocabulum 34: flute The recorder of a city.
1895		Crowe Aus. Sl. Dict. 30: Flute, the City Recorder.

2. (also German flute, silent flute) the penis.

c.1670		Broadside in Adlard Fruit of That Forbidden Tree (1975) 89: She will handle a flute / Better far than a lute / And make what was hard to grow tender.
1700		‘The Wanton Trick’ in Playford Pills to Purge Melancholy II 93: Thus she with her Lute, and he with his Flute, / Held every Crotchet and Prick.
a.1720		‘She Met with a Country-Man’ in Farmer Merry Songs and Ballads (1897) IV 258: He took her by the middle, / And taught her by the Flute.
1732-1820		Order of the Beggar's Benison and Merryland (1892) 28: Dinner Sentiments [...] Query — Do you know what Musical Instrument gives a Miss of 19 the highest satisfaction? Answer — A Flute, high-pitched and tightly held.
1736		Cupid 163: The Flute is good thats made of Wood / And is, I own, the neatest; / Yet neertheless I must confess, / The silent flute’s the sweetest [F&H].
1750		‘The Silent Flute’ in Button Hole Garland 6: Said he my Dear be Easy, / I have a Flute which tho’ ’tis Mute, / May play a Tune to please ye.
1767		Bridges Homer Travestie (2nd edn) I 107: Hoping a tune o’th’ silent flute / Would keep the scolding baggage mute.
1775		‘Miss Inglis’ in Ranger’s Impartial List of the Ladies of Pleasure in Edinburgh n.p.: She is remarkably fond of performing on the silent flute, and can manage the stops extraordinary well.
c.1785		‘The New Dhooraling’ in A. Carpenter Verse in Eng. in 18C Ireland (1998) 400: The Piper’s fees they never dispute / When he plays them a lilt on his German flute.
1788		Harris’s List of Covent-Garden Ladies 53: As neat a leg and foot as ever beat time to the silent flute.
1788		‘The Musical Piper’ Irish Songster 3: Your flutes out of order poor Mathew Malone.
c.1790		‘Davie Williamson’ Irish Ballads 4: His flute being long, and play’d so strong.
1819		Beppo in London liv: It was a patent Flute, and not on earth A finer shape’d one ever had been shaken – Besides ’twas perfect in the bottom keys, Which all musicians know are meant for C’s!
1833		‘The Primrose Girl’ in Fal-Lal Songster in Spedding & Watt (eds) Bawdy Songbooks (2011) III 24: I with my flute flew to her side, and on it I played quick, / Which charmed her to that degree, she laid hold of my [blank space].
1890–1904		Farmer & Henley Sl. and Its Analogues.
1897		School Life in Paris 91: The boy, whose tights instantly betray the movement sof his precociously developed ‘flute’.
1969		P. Boyle All Looks Yellow to the Jaundiced Eye 55: A copper is not at his best kneeling on the floor of a piss house with his flute hanging out.
1978		L. Kramer Faggots 320: Ding-dong, dingus, dink, dork, flute.
1990		R. Doyle Snapper 5: It was his flute tha’ – Daddy!
1998		P. McCabe Breakfast on Pluto 28: Girls didn’t really have any experience of boys and their electric little tootling flutes!
2001		G. Coughlan Everyday Eng. and Sl. 🌐 Flute (n): penis.

3. a pistol.

1837

‘Handy Andy’ in Bentley’s Misc. Apr. 375: ‘Where are the flutes?’ [...] ‘Here,’ said the squire, producing a very handsome mahogany case of Rigby’s best.

4. (US drugs) an opium pipe; thus hit the flute v., to smoke opium.

1881

San José Mercury 8 Oct. The foolish [...] boy [...] who deems it something smart to ‘visit a joint’ or ‘hit the flute.’.

5. (Aus.) a jockey’s whip; thus put the flute on v., to whip a horse.

1900–10

Stephens & O’Brien Materials for a Dict. of Aus. Sl. [unpub. ms.] 75: FLUTE slang / jockeys or other horsemen a whip. To put the flute on a horse is to flog him.

6. a police whistle.

1934		A. Bracey School for Scoundrels in DU.
1935		A.J. Pollock Und. Speaks.
1961		(con. 1920s) J. Sparks Burglar to the Nobility 77: The Bobbed Haired bandit could hear [...] the shouts and the flutes going — which is what we call the noise of prison screws blowing their emergency whistles.
1981		(con. 1900–30) A. Harding in Samuel East End Und. 282: Flute – Policeman’s whistle.

7. a male homosexual.

1937

R.B. Nye ‘A Musician’s Word List’ in AS XII:1 46: flute. A male homosexual.

8. (US police/NYPD) a a Coca-Cola bottle filled with liquor and povided free by a bar to a police supervisor.

1972		Knapp Commission Report Dec. 172: [I]t was not uncommon for policemen assigned to a radio car to pick up a ‘flute’—a Coke bottle filled with liquor—which they would deliver to the station house.
1973		L. Shecter On the Pad 94: A flute is like a Coke bottle full of whiskey. You go into a bar where they know you or know the lieutenant and you say to the bartender, I’d like to have a flute for the lieutenant. He’d go back, wash out a Coke bottle, fill it with whiskey, put a cork in it and give it to you.
1996		(con. 1965) J. Lardner Crusader 67: "I’m supposed to get a flute for Lieutenant Dalton [...] Can you tell me what a flute is?’ The bartender laughed, filled a Coke bottle with Scotch, sealed it with a cork [etc].