thumper

(countable, uncountable) One who thumps.
(countable, slang, uncountable) A single-cylinder engine, especially four-stroke engines or those with large engine displacements.
(uncountable) A drinking game wherein players must remember personal hand signs while being distracted by others banging on a table.
(countable, slang, uncountable) Something big, such as a lie; a whopper.
(UK, countable, slang, uncountable) A kind of slam-door train introduced in the late 1950s.
(US, countable, slang, uncountable) The Vietnam-era M79 grenade launcher (due to its distinctive report).
(countable, uncountable) A short rope for beating disobedient sled dogs.
(countable, informal, uncountable) A strong adherent to a religion or ideology.