The Collaborative International Dictionary of English v.0.48:

Nectarine \Nec"tar*ine\ (n[e^]k"t[~e]r*[i^]n), a.
   Nectareous. [R.] --Milton.
   [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Nectarine \Nec`tar*ine"\ (n[e^]k`t[~e]r*[=e]n"), n. [Cf. F.
   nectarine. See Nectar.] (Bot.)
   A smooth-skinned variety of peach.
   [1913 Webster]

   Spanish nectarine, the plumlike fruit of the West Indian
      tree Chrysobalanus Icaco; -- also called cocoa plum.
      It is made into a sweet conserve which is largely exported
      from Cuba.
      [1913 Webster]

WordNet (r) 3.0 (2006):

nectarine
    n 1: variety or mutation of the peach bearing fruit with smooth
         skin and (usually) yellow flesh [syn: nectarine,
         nectarine tree, Prunus persica nectarina]
    2: a variety or mutation of the peach that has a smooth skin