Arse Like The Store Horse Edit Meaning

1.

In Edinburgh,Scotland, a term to describe anyone, esp. female, who has a large posterior.

The 'Store', the Co-operative, was the cities major retailer of goods and employed horses and carts in the olden days to deliver goods etc.

'Morags looking no bad these days'

'Nah man, she's got an arse like the store horse'