Green’s Dictionary of Slang

lardy-dardy adj.

also lardi-dardy, lardy-di-dardy, lardy, lawdy-dawdy
[var. on la-di-da(h) adj. but actually earlier, so ? simply the sound of the speech]

affected, supercilious, foppish; thus as n., snobbishness, arrogance.

[UK]M.E. Braddon Trail of the Serpent 227: You’re not much good, my friend, says I, with your lardy-dardy ways, and your cold-blooded words, whoever you are.
[UK]Liverpool Dly Post 19 Mar. 1/2: Augustus Fitzfizgig, a lardy-dardy swell.
[UK]Sportsman (London) 7 Apr. 2/1: At the Newsvendors’ annual dinner [...] Mr Charles Dickens, who presided, [...] objected to the lawdydawdy fashion of ‘drinking wine’ with the company.
[UK]N. Devon Jrnl 23 Jan. 5/3: ‘Awfully Clever’ and the ‘Lardy Dardy Doo Swell’ were sung in character by Mr Fred Beckett.
[UK] ‘’Arry on Himself’ in Punch 21 Dec. in P. Marks (2006) 6: I’m dead on the high lardy-dardy, I loathes a straight-lacer or saint.
[UK] ‘’Arry on Crutches’ in Punch 3 May 201/1: This last lardy fashion, well there, – / It wouldn’t quite run to it, Charlie.
[UK]Essex Standard 26 Feb. 4/3: Anyone who knows what a tough-fought game is, will hardly agree with the idea that it is a ‘lardy-dardy’ amusement.
[UK] ‘’Arry at the Sea-Side’ in Punch 10 Sept. 111/2: To see lardy Toffs and swell ladies, and smart little girls with no fuss.
[US]Abilene Wkly Reflector (KS) 6 June 7/3: She hates the idea of any feller who’s only got lardy-dardy ways.
[Aus]H. Lawson ‘Possum’ in Roderick (1967–9) I 81: He sold ’is watch ’n’ jool’ry, ’n’ lardi-dardy suits.
[UK] ‘’Arry on Equality’ in Punch 22 Feb. 85/2: The skim-milk of life’s for the many, the lardy few lap up the cream.
[Scot]Aberdeen Eve. Exp. 29 Aug. 2/6: [headline] Lardy-Dardy Swell.
[UK]Taunton Courier 17 May 1/7: There’s the one-a-penny swell, / There’s the two-a-penny swell, / And the lardy-dardy party.
[UK]Marvel 16 June 579: I’m a lardy-di-dardy swell.
[UK]Liverpool Echo 27 Jan. 8/5: There is too much ‘lardy-dardy,’ too much doing the grand.
[US]Kurtis Blow ‘If I Ruled the World’ 🎵 I was dancing to the beat and entertaining, la-di-da-di.
[US]Sandy ‘Bad Boy’ 🎵 My mum she say the German man, him too lardy-dardy.

In phrases

come the lardy-dardy (v.)

1. to dress in a showy manner.

[UK]Partridge DSUE (1984) 243/2: from ca. 1860.

2. to behave in a supercilious manner.

[UK]Hull Packet 14 Dec. 3/1: The can’t allow the Mahdi / To ’come the lardy-dardy’.
do the lardy (v.)

to put on airs.

[UK] ‘’Arry in Switzerland’ in Punch 5 Dec. in P. Marks (2006) 97: Couldn’t patter her lingo — wus luck! — but I could do the lardy, and smile.