Sǽ-hengest

According to the Old English Dictionary:

es;

sǽ-hengest

m. I. a sea-horse, hippopotamus:--Sǽhengest ipotamus, Wrt. Voc. ii. 48, 30. II. a sea-steed, ship:--Hú ðú wǽgflotan, sǽhengeste, sund wísige, Andr. Kmbl. 975; An. 488. Cf. sǽ-mearh. sæ-hengest