filbert

Filbert is a synonym of hazelnut.

As nouns the difference between filbert and hazelnut

is that filbert is the hazelnut while hazelnut is the fruit of the hazel tree.

As nouns the difference between filbert and hazel

is that filbert is the hazelnut while hazel is a tree or shrub of the genus corylus , bearing edible nuts called hazelnuts or filberts.

As a adjective hazel is

of a greenish-brown colour (often used to refer to eye colour).