sousaphone
/ˈsuːzəˌfoʊn/
noun
- A large brass wind instrument similar to a tuba, with a wide bell that faces forward and a coiled body that wraps around the player, used especially in marching bands.
- The sousaphone player led the marching band with deep, booming notes.
- He lifted the heavy sousaphone onto his shoulder before the parade started.
- The sousaphone's distinctive sound gives a marching band its powerful bass line.