n.; pl.Deys [ Turk. dāi, orig., a maternal uncle, then a friendly title formerly given to middle-aged or old people, especially among the Janizaries; and hence, in Algiers, consecrated at length to the commanding officer of that corps, who frequently became afterward pasha or regent of that province; hence the European misnomer of dey, as applied to the latter: cf. F. dey. ] The governor of Algiers; -- so called before the French conquest in 1830. [ 1913 Webster ]