From The Ecylopaedia Judacia

A person who vows for a specific period to abstain from partaking of grapes or any of it's products whether intoxicating or not, cutting his hair, and touching a corpse (6:3-9)
Such a person is called a Nazirite (HEBREW nazir) from the root nzr meaning to separate or dedicate oneself (eg. , nifal,
Lev. 22:2 ; hifi. Lev. 15:31 Num. 6: 2
The subject is dealt with in the Priestly Code (Num. 6)