filbert /(?)/

fil·bert

filbert

n.
  1. The fruit of the Corylus Avellana or Corylus maxima, also called the hazel; the hazelnut. It is an oval nut, containing a kernel that has a mild, farinaceous, oily taste, agreeable to the palate. (Bot.)
  2. The tree bearing the filbert; the hazelnut tree. (Bot.)

Phrases & Compounds
Filbert gall
a gall resembling a filbert in form, growing in clusters on grapevines. It is produced by the larva of a gallfly (Cecidomyia).