Origin uncertain. 1. Possibly English, a habitational name from any of various minor places named Eastridge, for example in Wiltshire and West Sussex. However, the surname is not known in the British Isles. 2. It may alternatively be of German origin, an Americanized form of Estrich, a topographic name for someone who lived by a paved road (Middle High German esterich, from Late Latin astricus), or an Americanized form of Oesterreich.