For a discussion of the word, see Michael Freeman ‘Pots of Osey: Portuguese Wine in Late Medieval England and its Place of Origin’ in Stewart Gregory and D.A. Trotter, De Mot en Mot: Aspects of Medieval Linguistics, Cardiff, 1997, pp. 17-36. Freeman rejects the OED’s suggestion that the wine may have had its origin in Alsace (see also DMF), and links the word with Azoia, a vaguely defined area behind Lisbon.