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. [1913 Webster
" In England filberts are usually large hazelnuts, especially the nuts from selected and cultivated trees. The American hazelnuts are of two other species, Corylus Americana and Corylus cornuta, and are also sometimes called filberts."