It’s absolutely extending your power over a foreign nation. Resistance to domination is the enforcement of your own will over that of others. Wiki’s definition is intentionally vague to the point of being worthless, while the historical analysis of imperialism as originated with theorists like Hobson and extended by Lenin, Nkrumah, and Cheng Enfu describes an actual system, its material causes and mechanisms, and describes why it exists and how to end it. The wiki definition is like defining capitalism as “trade” and saying Marx was being ridiculous by analyzing it further.

Here’s a good summary of imperialism. Treating imperialism like a vibe, and not like a material process, means we are incapable of learning how to stop it.