1 Irish: reduced form of McCambridge .2 English: habitational name for someone from either of two places called Cambridge: one in Gloucestershire, the other in Cambridgeshire (the university city). Until the late 14th century the latter was known as Cantebrigie ‘bridge on the (river) Granta’, from a Celtic river name meaning ‘marshy river’. Under Norman influence Granta- became Cam-. It seems likely, therefore, that the surname derives mainly from the much smaller place in Gloucestershire, recorded as Cambrigga ( 1200–10 ), and named for the Cam, a Celtic river name meaning ‘crooked’, ‘winding’.
LOAD TEST -- Dictionary of American Family Names © Patrick Hanks 2003, 2006.