1. noun Someone or something that holds immense, irresistible, and merciless force or power. Alluding to the unstoppable nature of a literal steamroller. The country's huge military has become a steamroller, wiping out nearly every other country in the region. The team's defensive tackle is an absolute steamroller, pushing offensive linemen aside like they were children.

2. verb To move forward with destructive, crushing force. The tank just steamrollered through the town, smashing everything in its path.

3. To progress with relentless, overpowering force. The unlikely political candidate has steamrollered through the elections, eliminating every opponent that has stood in her way.

4. To cause something to be accepted, passed, adopted, etc., by relentless, overpowering force. The political party is trying to steamroller the legislation through Congress.