The policy of extending a nation's authority by territorial acquisition or by the establishment of economic and political hegemony over other nations.
The system, policies, or practices of such a government.
American Heritage(R) Dictionary of the English Language, Fifth Edition. Copyright (c) 2011 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.