- [Bot] A shrub or small tree of the genus Corylus, as the Corylus avellana, bearing a nut containing a kernel of a mild, farinaceous taste; the filbert. The American species are Corylus Americana, which produces the common hazelnut, and Corylus rostrata. See Filbert.
- A miner's name for freestone.
Etymology: OE. hasel, AS. hæsel; akin to D. hazelaar, G. hazel, OHG. hasal hasala, Icel. hasl, Dan & Sw. hassel, L. corylus, for cosylus