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.]