Dass

I just returned from Scotland where I had an opportunity to view a 12th century stone built barn with timber roof structure.
The building was split into sections or bays but the farmer referred to these as "dass" and not "bay".

I know that a great many Scottish vernacular words are still at large and used everyday in America and Canada e.g. couch, stook,

Has anybody ever heard this word in use ?

Regards

Ken Hume