Cayey (kīā`), town (1990 pop. 46,553), SE Puerto Rico, in the Sierra de Cayey Mts. It is a sugar, tobacco, and poultry center and a summer resort. Cigars and clothing are manufactured. Founded in 1774, it is the seat of Cayey Univ. College, a branch of the Univ. of Puerto Rico. Outside the town is a U.S. military reservation, Henry Barracks.