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
1. To graft; to insert as a scion. [Obs.] --Rom. of R.
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]
Imp out our drooping country's broken wing. --Shak.
Who lazily imp their wings with other men's plumes.
Here no frail Muse shall imp her crippled wing.
Help, ye tart satirists, to imp my rage
With all the scorpions that should whip this age.