Not \Not\, adv. [OE. not, noht, nought, naught, the same word as E. naught. See Naught.]

A word used to express negation, prohibition, denial, or refusal.

Not one word spake he more than was need. --Chaucer.

Thou shalt not steal. --Ex. xx. 15.

Thine eyes are upon me, and I am not. --Job vii. 8.

The question is, may I do it, or may I not do it? --Bp. Sanderson.

Not . . . but, or Not but, only. [Obs. or Colloq.]

--Chaucer.

Source: Webster's Revised Unabridged Dictionary (1913)