slang. [Onomatopœic, in ridicule of ‘swell’ modes of utterance. Cf. HAW-HAW.] A derisive term for one who affects gentility; a ‘swell.’ Also attrib. or adj. = LARDY-DARDY.

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1881.  Daily Inter Ocean, 8 March, 4/6. Not the languid la-di-da drawl of the would-be swell.

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c. 1883.  in Atkin, House Scraps (1887), 166.

        The young ’un goes to music-halls,
    And does the la-di-da.

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1893.  Gunter, Baron Montez, III. viii. 77. That French brother of his, Frank, the Parisian la-de-da.

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1895.  Westm. Gaz., 31 Jan., 3/2. I may tell you we are all homely girls. We don’t want any la-di-da members.

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