TREVYVIAN, TREVIVION.  Pryce renders the latter name, the dwelling by the small water (vy-bian).  I derive these names from tre-Vyvian, the dwelling of Vivian.  There is a place called Trevivian in Davistow.
    VYVIAN, VYVYAN.  "The Vyvians of Truro are derived by certain genealogists from one Vivianus Annius, a Roman general, son-in-law of Domitius Carbulo."  (Quar. Rev. c. 11, p. 304.).  Others consider the name to be from Cornish vyvyan, to flee.  Polwhele, under chuyvyan, "to escape, to fly," says, "Hence Vyvian, flying on a white horse from Lyonesse when it was inundated, is said to have derived his name.  He was then governor of Lyonesse.  The family of Vyvian gives a lion for its arms, and a white horse, ready capaprisoned, for its crest, in memory of that incident."  The name has also been derived from vy-vian, the small water.  (See Trevivion.)  Vyvyan, Viuian, Vivin, Viven, are different orthographies of the name. (Patronymica Cornu-Britannica, Charnock, 1870)