de ‧ pop ‧ u ‧ late /ˌdiːˈpɒpjəleɪt, ˌdiːˈpɒpjʊleɪt $ -ˈpɑːp-/ BrE AmE verb [transitive usually passive]
to greatly reduce the number of people living in a particular area:
Disease depopulated the whole region.
—depopulation /diːˌpɒpjəˈleɪʃ ə n, diːˌpɒpjʊˈleɪʃ ə n $ -ˌpɑːp-/ noun [uncountable]