To monopolize means to take complete control of something, leaving nothing for anyone else. When one student monopolizes the teacher's attention by constantly raising their hand and asking questions, other students don't get a chance to participate. When someone monopolizes the conversation at dinner, they talk so much that nobody else can share their stories.

If one company monopolized the production of bicycles, no other bicycle makers could survive, and customers would have no choice about where to buy. Governments often make monopolies illegal because they eliminate competition and can lead to unfair prices.

In everyday use, monopolize usually carries a negative tone. It suggests selfishness or thoughtlessness, like a kid who monopolizes the basketball at recess instead of passing it, or a sibling who monopolizes the remote control all evening.