'Hampstead' simply means homestead.
It comes from the Anglo-Saxon words ham and stede; Berkhamsted and Wheathampstead are similar names. Hampstead appears in a grant by King Ethelred the Unready of 986 and in the Domesday Book of 1086. The name Heath Street was proposed for the station before it opened in 1907, and its old platform tiles still read Heath Street. It has the deepest platforms on the Underground.