colonialism

from The American Heritage® Dictionary of the English Language, 5th Edition.

• noun The policy or practice of a wealthy or powerful nation's maintaining or extending its control over other countries, especially in establishing settlements or exploiting resources.

from The Century Dictionary.

• noun A practice, idiom, or phrase peculiar to a colony.
• noun Collectively, the characteristics of colonial life.
• noun The colonial principle or system: as, British colonialism works well.

from the GNU version of the Collaborative International Dictionary of English.

• noun The state or quality of, or the relationship involved in, being colonial.
• noun A custom, idea, feature of government, or the like, characteristic of a colony.
• noun The colonial system of political government or extension of territory, by which one nation exerts political control over another nation, territory, or people, maintaining the colony in a state of dependence, its inhabitants not having the same full rights as those of the colonial power. The controlling power is typically extended thus by military force or the threat of force.
• noun the political or ideological system of beliefs advocating or justifying colonial control of one nation over another nation, territory, or people.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• noun The colonial domination policy pursued by the powers of Europe, from the second half of the XIX century to the years following World War II. A colonial system.
• noun A colonial linguistic expression. Term or expression of colonial origin entered in a language.
• noun Colonial life.

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

• noun exploitation by a stronger country of weaker one; the use of the weaker country's resources to strengthen and enrich the stronger country