Green’s Dictionary of Slang

stern n.

also sternpost

1. the buttocks; thus -sterned sfx, having buttocks of a specified kind.

[UK]Spenser Faerie Queene Bk I Canto xi Stanza 28: He [...] gan his sturdy sterne about to weld.
[UK]N. Ward ‘A Step to Stir-Bitch-Fair’ in Writings (1704) 257: She acquiesc’d her Dutch-built Stern into a Sedential posture at the Upper-end of the Table.
[UK]Humours of a Coffee-House 17 Oct. 378: If you don’t like my Tale, you may kiss my Stern.
[UK]Bridges Burlesque Homer (4th edn) I 42: Patroclus, fetch this square-stern’d jade.
[UK]‘An Officer of the Line’ Military Sketch-book I June c.207: ‘Here’s this bl—y Murphy stickin’ a sword into my stairn’.
[US]Ely’s Hawk & Buzzard (NY) Sept. 6 n.p.: Her corporation drawn in and her stern bulged out.
[UK]‘Tim Snip’ in Cove in Spedding & Watt (eds) Bawdy Songbooks (2011) IV 216: He went to the window, his stern there did place, / Which Tim kiss’d, tho’ he thought she had a swell’d face.
‘The Saucy Hell-Cat and the Indiaman’ in Lloyd’s Companion 19 Sept. 2/4: [B]ringing his pistol into juxtaposition with his companion’s stern.
[UK]Peeping Tom (London) 17 66/2: Then Ann did turn, upon her stern.
[Aus]Bell’s Life in Sydney 4 July 3/2: ‘I’ve Bought the Ring’ Words by Bosh. Music by Frozenstern.
[UK]R.S. Surtees Plain or Ringlets? (1926) 315: Jonathan then hoisted his great sternpost into the saddle.
Furnivall Book of Precedence (E.E.T.S.) Forewords xxiii: We don’t want to deceive ourselves about them, or fancy them cherubs without sterns [F&H].
[UK]‘Old Calabar’ Won in a Canter I 263: Nothing was now to be seen of the pack but their sterns feathering in the thick gorse [Ibid.] 264: [T]he hounds were well away on a burning scent, with their heads up and sterns down.
[Aus]Dead Bird (Sydney) 10 Aug. 1/4: ‘You speak of the general “with her stern front,” and what we want to know is, how could any one have his stern in front?’.
[UK](con. 1836) Regiment 16 Apr. 47/2: First and foremost, our tails—they hung from our heads to our sternpost—all the ship’s company wore them.
[UK]Athenaeum 8 Feb. 176 3: He was taught nothing, except that jumping to any word of command saved his bows from cuffing, his stern from kicking [F&H].
[Aus]Sydney Sportsman (Surry Hills, NSW) 16 Nov. 8/7: A girl in flimsy silk so white / [...] / Pulled tight around an ample stern.
[UK]‘Taffrail’ Sub 88: I’ve ’urt me stern somethin’ crool.
[US]T. Wolfe Look Homeward, Angel (1930) 191: Among those dancing were [...] Messrs. I.C. Bottom, U.B. Freely, R.U. Reddy, O.I. Lovett [...] and J. Broad Stern.
[Aus]K. Tennant Battlers 79: Here’s Dick and me been sitting on our sterns all day waiting for the cow, and he don’t show up.
[Aus]D. Stivens Jimmy Brockett 110: Her stern moved under her dress like a couple of water melons.

2. the anus.

[UK]‘Ramrod’ Nocturnal Meeting 91: A copious injection into the two plump sterns.

In compounds

sternpost (n.) [naut. imagery]

1. the buttocks.

[Ire]‘A Real Paddy’ Real Life in Ireland 244: The two worthies turned their sternposts to the fire, as it is very customary in Ireland for gentlemen to do.
[UK]Navy at Home I 141: The stocking — which now ballasted with a pound or so of sand, was seen flying back in the air and descending with a vengeance on the greater delinquent's stern post.

2. the penis.

[UK]Farmer & Henley Sl. and Its Analogues.
sternwheeler (n.) [play on SE sternwheeler, a boat propelled by a wheel at its rear]

(US gay) a passive male homosexual.

[US]Goldin et al. DAUL 210/1: Stern-wheeler. (Mississippi Valley) A passive pederast.
[US]Maledicta III:2 233: Still more words of this fucking vocabulary are [...] sternwheeler.

In phrases