Etymology: Old English impa (or ? impe ), plural impan , goes with impian (see imp v.). Compare also modern German impf, Danish ympe, Swedish ymp. Welsh imp graft, scion, is from Middle English; French ente (whence Middle Dutch ente, Dutch ent) is ultimately from the same source.

Etymology: Old English impian (rare) = Old High German impfôn (rare), Middle High German and German impfen, beside which Old High German had (more commonly) impitôn, Middle High German imp(e)ten. Danish ympe, Swedish ympa are from a Low German *impen; Welsh impio is from English. French enter (whence Middle Dutch enten, inten, Dutch enten, Middle Low German enten) is supposed to be ultimately from the same source. The history of this verb and imp n.¹ is in some points obscure, from want of evidence. The corresponding French enter to graft, ente (for *empte) graft, are referred by Darmesteter, etc., to late Latin *emputāre, *emputa, the latter neuter plural of Greek ἔμϕυτος, ἔμϕυτον implanted, engrafted: compare ἐμϕύειν to implant, ἐμϕυτεύειν to implant, engraft, ἐμϕυτεία implanting, engrafting. (There is evidence in the Salic Law for a medieval Latin impotus, inpotus, scion, graft.) This was presumably the source also of Old High German impitôn (not impfitôn), Middle High German imp(e)ten; though some would refer it to Latin putāre to prune. Old English impian, Old High German impfôn, was evidently, from the Old High German lautverschiebung, a word of earlier adoption, but was probably derived in some way from the same Greek source (? < ἐμϕύειν); of this the Old English n. impa (hardly impe) must then have been a derivative, on the analogy of agent-nouns in -a; so modern German impf < impfen.