The Collaborative International Dictionary of English v.0.48:

Imp \Imp\, v. t. [imp. & p. p. Imped; p. pr. & vb. n.
   Imping.] [AS. impian to imp, ingraft, plant; akin to Dan.
   ympe, Sw. ympa, OHG. impf[=o]n, impit[=o]n, G. impfen. See
   Imp, n.]
   1. To graft; to insert as a scion. [Obs.] --Rom. of R.
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   2. (Falconry) To graft with new feathers, as a wing; to
      splice a broken feather. Hence, [Fig.]: To repair; to
      extend; to increase; to strengthen; to equip. [Archaic]
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            Imp out our drooping country's broken wing. --Shak.
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            Who lazily imp their wings with other men's plumes.
                                                  --Fuller.
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            Here no frail Muse shall imp her crippled wing.
                                                  --Holmes.
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            Help, ye tart satirists, to imp my rage
            With all the scorpions that should whip this age.
                                                  --Cleveland.
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