BATAC, a municipality (with administration centre and 35 barrios or districts) of the province of Ilocos Norte, Luzon, Philippine Islands, I 2m. S. of Laoag the capital. Pop. (1918), 23,986, of whom 10,962 were males and four whites. Tobacco and rice are among the most important products, and there is a considerable trade in these and other commodities. Sugar, fans and woven fabrics are manufactured. In 1918 it had 32 house hold industry establishments, with output valued at 8,000 pesos; and 14 schools, all public. Batac was founded in 1587. It is the birthplace of Gregorio Aglipay (b. 186o), the founder of the schismatic Filipino Independent Church. The language is I1ocano.