Green’s Dictionary of Slang

1. boots or shoes.

1789		G. Parker Life’s Painter v. 36: He [i.e. a cobbler] had frequently furnished men of the first rank (bishops not excepted) with understandings of the best sort.
1824		Pierce Egan’s Life in London 26 Dec. 381/3: This patcher of queer understandings.
1838		J. Grant Sketches in London 87: His toes began to peep out between the soles and uppers of his ‘understandings’ — as he sometimes facetiously called his boots.
1857		Bell’s Life in Sydney 9 May 2/3: We prefer to go to the approved boot-maker to improve our ‘understandings’ rather than appeal to the pretensious [sic] ‘snob’.
1861		Dundee, Perth &Cupar Advertiser 14 May 7/5: Bright understandings!!! Harper Twelvetrees’ New Government Blacking As supplied to the Horse Guards.
1872		Fife Herald 24 Oct. 3/1: On awakening [he] found he was minus his boots! It is conjectured that some needy tramp had eased him of his understandings.
1873		Sl. Dict. (5th edn) 333: Men who wear exceptionally large or thick boots, are said to possess good understandings.
1874		Dover Exp. 25 Sept. 1/4: Coulthard and Wilson’s Poetic Appeal to the ‘Understandings’ of the People. ‘Boots and Shoes in beauty rare [...] Boots and Shoes in leather strong’.
1886		Derby Dly Teleg. 11 May 1/5: Sound understandings, remarkably cheap, will wear the floor out, only at Crooks’.
1892		Hull Dly Mail 12 Jan. 3/3: ‘What would you do if you were in my shoes, Jephson?’ asked Hobbs. ‘Black ’em,’ replied Jephson, eyeing Hobbs’ understandings critically.
1895		Crowe Aus. Sl. Dict. 90: Understandings [...] one’s boots.
1909		Hull Dly Mail 29 Apr. 2/4: Good Understandings [...] ‘Benefit’ Boots and Shoes.
1942		Western Dly Press 26 May 2/3: [headline] Good Understandings. Big Increase in Boot Repairs.

2. the legs.

1828		Lancet 22 Mar. 920/1: He moves on, his plump, well-formed, little ‘understandings’ twinkling in the lustre of black silk hose .
1838		R. Nicholson Cockney Adventures 13 Jan. 87: A lady [...] sat opposite, with her understandings encased, as Nancy very properly suspected, in the fine white hose.
1841		True Flash (NY) 4 Dec. n.p.: A man who had hobbled about on wooden pegs [...] took a whole bottle of the ‘Elixir of Life’ and [...] found himself the next morning dancing on a pair of natural understandings.
1845		R.S. Surtees Hillingdon Hall I 129: Unless a man spends ’alf his time at ’Owell and James’s, or Swan and Hedgar’s [...] waitin’ for to see the gals get into their chays, he has no possible chance o’ knowin’ wot sort o’ understandin’s they have.
1855		Broadway Belle (NY) 1 Jan. n.p.: Lizzie [...] must wear high boots that will conceal her captivating understandings.
1866		Illawarra Mercury (Wollongong, NSW) 18 Sept. 4/1: A racehorse with damaged legs is described [...] as ‘done up in his pins’ and [...] ‘weak in his understanding,’ or ‘shaky in his timbers’.
1867		Wrexham Advertiser 2 Mar. 7/1: In the language of the prize-ring [...] a man has not [...] legs, but ‘pins’ or ‘understandings’s.
1880		Bulletin (Sydney) 30 Oct. 8/3: The ‘understandings’ displayed by Miss Annie Montague [...] on the boards of the Melbourne Opera House, are something to dream of.
1880		Nat. Police Gaz. (NY) 9 Oct. 13: [pic. caption] Mrs Jane Sanders Hires a Coupe [...] Shoves Her Feet through the Window and Exposes a Pair of Understandings That Electrify a Cabby.
1886		Field 20 Mar. n.p.: Economy’s understandings having given way soon after, he knew the silk no more [F&H].
1890		Dead Bird (Sydney) 12 Apr. 4/3: A well-known masher [...] tried to dance a Scotch reel on wheels that Gracie might notice his understandings [...] his Scotch kilts flopping in the breeze.
1895		Crowe Aus. Sl. Dict. 90: Understandings, feet [sic].
1903		Bulletin (Sydney) 2 July 34/4: I have made the alarming discovery that nearly 75 per cent. of Sydney is gone in the legs! One of my own understandings being out of gear, I’m instinctively interested in those of others.
1905		Sun. Times (Perth) 25 June 1/1: The shapely understandings of a Newcastle nymph have caused a great thrill.
1912		Bulletin (Sydney) 12 Dec. 24/4: Stockings that furnish glimpses of ankles white and neat, / When those shapely understandings go pattering down the street.
1922		Joyce Ulysses 355: Typist going up Roger Greene’s stairs two at a time to show her understandings.