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imperialistic

American  
[im-peer-ee-uhl-ist-ik] / ɪmˌpɪər i əlˈɪst ɪk /

adjective

  1. seeking to extend the rule of an empire over foreign countries or to acquire and hold colonies.

  2. promoting the interests of an empire or of a colonial or postcolonial power over the interests of its dependent states or populations.