BATAC, a town of the province of Ilocos Norte, Luzon, Philippine Islands, 10 m. S. of Laoag, the capital. Pop. (1903) 19,524; subsequently, in October 1903, the town of Banna (pop. 4015) was annexed. Cacao, tobacco, cotton, rice and indigo are grown in the neighbouring country, and the town has a considerable trade in these and other commodities; it also manufactures sugar, fans and woven fabrics. Batac was founded in 1587. It is the birthplace and home of Archbishop Gregorio Aglipay (b. 1860), the founder of an important sect of Filipino Independent Catholics.