\Doss\, n. (Etym. uncertain.)
A place to sleep in; a bed; hence, sleep.
This traditional meaning has slipped somewhat out of everyday usage, and the meanings elaborated in other WUs seem to be more prevalent. It is only used in its traditional form in the north east of Scotland, where it is still common to here people say "I'm off tay mi doss.", meaning "I'm going to bed."
Thurs Jun 2002 at 18:50 Update:
Oolong informs me that Chambers Dictionary has the etymology of this word.
I quote Oolong who quotes Chambers Dictionary;
'Perh. from doss, a dial. English name for a hassock; or perh. dorse (see under dorsal)'