[im.pe.ri.al.ism] n (1851) 1: imperial government, authority, or system
2: the policy, practice, or advocacy of extending the power and dominion of a nation esp. by direct territorial acquisitions or by gaining indirect control over the political or economic life of other areas; broadly: the extension or imposition of power, authority, or influence "union ~" -- im.pe.ri.al.ist n or adj -- im.pe.ri.al.is.tic adj -- im.pe.ri.al.is.ti.cal.ly adv