"A Wee Deoch an Doris"

There's a good old Scottish custom that has stood the test o'time,
It's a custom that's been carried out in every land and clime.
When brother Scots are gathered, it's aye the usual thing,
Just before we say good night, we fill our cups and sing...

Chorus
Just a wee deoch an doris, just a wee drap, that's a,
Just a wee deoch an doris afore we gang awa.
There's a wee wifie waitin' in a wee but an ben.
If you can say, "It's a braw bricht moonlicht nicht,"
Well yer a'richt, ye ken
.

Harry Lauder made this song famous. You can hear him sing it here (on Youtube).

- from Scottish Gaelic deoch an doruis 'drink at the door'. Note the cognate doruis - door.