OLOOSSON(Ὀλοοσσών: Eth. Ὀλοοσσόνιος), a town of Perrhaebia in Thessaly, mentioned by Homer, who gives to it the epithet of white,from its white argillaceous soil. In Procopius the name occurs in the corrupt form of LOSSONUSI t is now called Elassóna, and is a place of some importance. It is situated on the edge of a plain near Tempe, and at the foot of a hill, on which there is a large ancient monastery, defended on either side by a deep ravine. The ancient town, or at least the citadel, stood upon this hill, and there are a few fragments of ancient walls, and some foundations behind and around the monastery. (Hom. Il. 2.739; Strab. 9. p. 440; Lycophr. 905; Steph. B. s. v.;Procop. de Aedif. 4.14; Leake, Northern Greece, vol. 3. p. 345.)