From the Spanish and Portuguese name Teresa. It was first recorded as Therasia, being borne by the Spanish wife of Saint Paulinus of Nola in the 4th century. The meaning is uncertain, but it could be derived from Greek θερος (theros) "summer", from Greek θεριζω (therizo) "to harvest", or from the name of the Greek island of Therasia (the western island of Santorini).