Noun
English Wikipedia has an article on:Ordnance SurveyWikipedia
Ordnance Survey map (plural Ordnance Survey maps)
any of a large series of high quality, detailed maps of Great Britain produced in a variety of scales originally for military, but now for leisure or business use
If you’re a fan of a good old Ordnance Survey map, then this might well be the GPS device for you. Source: Internet