Dictionary Definition

filbert

1 small nut-bearing tree much grown in Europe [syn: cobnut, Corylus avellana, Corylus avellana grandis]

2 nut of any of several trees of the genus Corylus [syn: hazelnut, cobnut, cob]

User Contributed Dictionary

The hazelnut is called a filbert because the plant blooms on St. Filbert’s Day in parts of the Near East.

filbert

A small nut that grows on large bushes. The hazelnut. (usually the American Hazel (Corylus americana) which is common in Oregon.)
A paintbrush used in oil and acrylic painting with a long ferrule and a curving, tongue-shaped head.

cobnut (usually the Common Hazel (Corylus avellana) which grows in the UK and Europe.)
hazelnut

Filbert can mean the following:

Corylus maxima, a species of hazel
Filbert, West Virginia
a type of artists' paintbrush with an elongated flat bristle with a rounded or circular tip
Filburt, a character of the TV show Rocko's Modern Life
Slang: a lunatic; an individual wholly unhinged; predominant neurotic tendencies (e.g., "a nut").