The story
- Scots · derived fromauld lang syne“old long ago”
- English todayauld lang syne
From Scots auld lang syne (“old long ago”, literally “old long since”), popularized by the poem “Auld Lang Syne” (1788) by Scottish poet and lyricist Robert Burns (1759–1796) based on an older song.
Etymology from Wiktionary, CC BY-SA 4.0.