slang. [prob. f. FLY v.1, though the etymological notion is doubtful.]

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  1.  Knowing, wide-awake, sharp. Fly to (anything): ‘up’ to, well acquainted with, clever at.

2

1811.  Lexicon Balatronicum, s.v. Fly.… The rattling cove is fly; the coachman knows what we are about.

3

1825.  C. M. Westmacott, Eng. Spy, II. 5.

        You’ve told the town that you are fly
To cant, and rant, and trickery.

4

1851.  Mayhew, Lond. Labour, II. 109. There ’s lots taken in about good-wills, but perhaps not so many in my way of business, because we ’re rather ‘fly to a dodge.’

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1852.  Dickens, Bleak House, xvi. ‘I am fly,’ says Jo.

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  2.  Of the fingers: Dexterous, nimble, skilful.

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1834.  W. H. Ainsworth, Rookwood, III. v., ‘Jerry Juniper’s Chaunt.’

        Fogles and fawnies soon went their way,
                    Fake away,
To the spout with the sneezers in grand array,
No dummy hunter had forks so fly;
            Nix my doll palls, fake away.

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1839.  G. W. M. Reynolds, Pickw. abroad, 224.

        The richest cribs shall our wants supply—
Or we’ll knap a fogle with fingers fly,
  When the swell one turns his back.

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  3.  Comb. as fly-flat (see quot.).

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1889.  Barrère & Leland, Slang Dict., Fly-flat (turf), one who really knows little or nothing about racing, but fancies himself thoroughly initiated in all its mysteries.

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