The Collaborative International Dictionary of English v.0.48:

Avellane \A*vel"lane\, a. [Cf. It. avellana a filbert, fr. L.
   Avella or Abella a city of Campania.] (Her.)
   In the form of four unhusked filberts; as, an avellane cross.
   [1913 Webster] Ave Maria

WordNet (r) 3.0 (2006):

avellane
    adj 1: pertaining to filberts or hazelnuts [syn: avellan,
           avellane]