Brainpower rhymes with:
manpower, airpower, firepower, horsepower, manpower, seapower, willpower, airpower, belflower, bellflower, cauliflower, coneflower, cornflower, eisenhower, fillauer, firepower, hightower, horsepower, hufbauer, icenhower, landauer, manpower, mayflower, safflower, seapower, sunflower, wallflower, wildflower, willpower, zembower