a. [ Cf. F. colonial. ] Of or pertaining to a colony; as, colonial rights, traffic, wars. [ 1913 Webster ]

n. 1. The state or quality of, or the relationship involved in, being colonial.

The last tie of colonialism which bound us to the mother country is broken. Brander Matthews. [ Webster 1913 Suppl. ]

2. A custom, idea, feature of government, or the like, characteristic of a colony. [ Webster 1913 Suppl. ]

3. 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. [ Webster 1913 Suppl. +PJC ]

4. the political or ideological system of beliefs advocating or justifying colonial control of one nation over another nation, territory, or people. [ PJC ]

n. a believer in or advocate of colonialism{ 3 }. [ WordNet 1.5 ]