Tibet /tɪˈbɛt/ noun3 •A geographic region in Central Asia (mostly in China), the homeland of the Tibetan people, covering much of the Tibetan Plateau. •An autonomous region of China. Official name: Tibet Autonomous Region. Capital: Lhasa. •(historical) A former country in East Asia that existed from 1912 until its annexation by China in 1951.The estimated population of the Chinese Empire (exclusive of Tibet) is given, on the basis of this census, as 329,542,000, while the population of Tibet is estimated at 1,500,000. — 1922