Dibrugarh (dĬb´rŏŏgər), city (1991 pop. 125,667), Assam state, NE India, at the confluence of the Brahmaputra and Bibru rivers. The town is on a narrow plain adjacent to hills and is often threatened by monsoon floods. It is a district administrative center and a terminus for rail and river traffic. There are four airfields, which were used by the British against Japanese forces in Myanmar during World II. Dibrugarh is surrounded by tea plantations and has tea factories and rice and oilseed mills. There is some coal mining and petroleum production.