Source : Webster's Revised Unabridged Dictionary (1913)

Plumcot \Plum"cot\, n. [Plum + apricot.] (Hort.)
   A cross between the plum and apricot.

Source : WordNet®

plumcot
     n 1: hybrid produced by crossing Prunus domestica and Prunus
          armeniaca [syn: {plumcot tree}]
     2: hybrid between plum and apricot