Source : Webster's Revised Unabridged Dictionary (1913)

Syne \Syne\, adv. [See {Since}.]
   1. Afterwards; since; ago. [Obs. or Scot.] --R. of Brunne.

   2. Late, -- as opposed to soon.

            [Each rogue] shall be discovered either soon or
            syne.                                 --W. Hamilton
                                                  (Life of
                                                  Wallace).

Syne \Syne\, conj.
   Since; seeing. [Scot.]