loudspeaker

noun3

1. •
   An electromechanical transducer that converts an electrical signal into audible sound.

   • Unintelligible announcements on station loudspeakers are both irritating and confusing. — 1953
2. •
   Any such transducer that is loud, as opposed to quiet ones such as those found in headphones.
3. •
   An encasing containing one or more loudspeaker devices and usually other electrical equipment such as a driver.