Abacá (English pronunciation: /ɑːbəˈkɑː/ ah-bə-KAH, from Spanish "abacá" for Musa textilis) is a species of banana native to the Philippines, grown widely as well in Borneo and Sumatra. It is sometimes referred to as "BacBac". The plant is of great economic importance, being harvested for its fibre, once generally called Manila hemp, extracted from the leaf sheath around the trunk. On average, the plant grows about 20 feet (6 metres) tall. The fibre was originally used for making twines and ropes as well as the Manila envelope; now most abacá is pulped and used in a variety of paper-like products including filter paper and banknotes. It is classified as a hard fibre, along with coir, henequin and sisal. The plant's name is sometimes spelled Abaká.

Abacá was first cultivated on a large scale in Sumatra in 1925 under the Dutch, who had observed its cultivation in the Philippines for cordage since the 1800s, followed up by plantings in Central America sponsored by the U.S. Department of Agriculture. Commercial planting began in 1930 in British North Borneo; with the commencement of WWII, the supply from the Philippines was eliminated by the Japanese.

Other common names for abacá or Manila hemp include "Cebu hemp" and "Davao hemp".