(perhaps 'place of the yew trees') became Anglo-Saxon Eoforwic ('Boar-town'), then Old Norse Jorvik ('Horse-bay'), and modern English York. Elaboration of place names often occurred to make distinctions between similarly named settlements. For instance, in England, two nearby and related settlements often became 'lower/nether' and 'upper/higher'; or 'little' and 'great' (or the equivalent in Latin, parva and magna). Alternatively, two geographically separated places might be distinguished by local features; e.g. Newcastle-under-Lyme and Newcastle upon Tyne; or Newton-le-Willows, Newton-by-Frodsham, Newton under Roseberry (and so on). In England, many additions were made in the medieval period, to show that settlements were ruled by certain families, e.g. as Stoke Mandeville. Some elaborations (particularly in Latin) date back to medieval times, such as Weston-super-Mare ('Weston-on-sea'), while others were added relatively recently, for instance Bognor Regis ('Bognor of the King'). Backformation: the process whereby names are derived from one another in the opposite direction to that which would be expected - in many cases a river with an obsolete or forgotten name is renamed after a town on its banks rather than vice versa. For example, the river running through Rochdale became known as the 'Roch' through this process. Cambridge perhaps uniquely illustrates both normal and back formation. Originally Grantabrice, a bridge on the Granta, the name became Cantebrugge, and then Cambrigge, from which the river was renamed 'Cam'. Problems of interpretation Place names often need specialists to interpret their meanings. Some of the main problems are: Language. Sometimes the language used in the formation of a place name is unclear; for example, some names may be plausibly derived from either Old English or Celtic roots. In recent years there has been a tendency to seek Celtic origins for names in England that were previously taken to be Anglo-Saxon. Element order. In Germanic languages, and thus in Old English and Old Norse, the substantive element is generally preceded by its modifier, such as "north farm" (Norwich), "Badecca's spring" (Bakewell). In Celtic place names the order is usually reversed with the thing being described (hill, valley, farm, etc.) as the first element, for example "settlement of the Cuebris" (Tregonebris), "mouth of the Dee" (Aberdeen). However, this is not true of all Celtic names, for example "bald hill" (Malvern). Translation. The general similarity of Old Norse and Old English meant that the place names in the Danelaw were often simply "norsified". For instance, in Askrigg ('ash (tree)