From Longman Dictionary of Contemporary Englishspeedboatspeed‧boat /ˈspiːdbəʊt $ -boʊt/ noun [countable] 
TTWa small boat with a powerful engine, designed to go fast
TTWa small boat with a powerful engine, designed to go fastExamples from the Corpus
speedboat• Then the police will start spending the money on helicopters and speedboats.• Eventually they became accustomed to the short trip to it by speedboat, the audience watching them from the casino.• Biscuits are big, fat inner tubes pulled by speedboats.• Why would Jeff and Silvia have taken the speedboat there?• The door to the boathouse where the speedboat was kept hung open, swaying drunkenly on its broken hinges.• In the Malacca strait two speedboats showing no lights approached a bulk carrier from the stern at night. 