Meaning of "Auld Lang Syne"

times long past.

auld lang syne

ôld′ lăng zīn′, sīn′
auld lang syne  (ôld′ lăng zīn′, sīn′)
n.
The times gone past; the good old days.

[Scots : auld, old + lang, long + syne, since.]

auld lang syne

ˈɔːld læŋ ˈsəɪn; ˈsaɪn; ˈzaɪn
auld lang syne (ˈɔːld læŋ ˈsəɪn; ˈsaɪn; ˈzaɪn)
n
old times; times past, esp those remembered with affection or nostalgia
[Scottish, literally: old long since]

auld lang syne

(ˈɔld læŋ ˈzaɪn, ˈsaɪn)
auld lang syne (ˈɔld læŋ ˈzaɪn, ˈsaɪn) n.
fondly remembered times.
[Scot: literally, old long since, i.e., old long-ago (days)]