sou·sa·phone (sōō'zə-fōn', -sə-) n. A large brass wind instrument, similar in range to the tuba, having a flaring bell and a shape adapted to being carried in marching bands.
1925, named for U.S. bandleader and composer John Philip Sousa (1854-1932).
"The first sousaphone was made by C. G. Conn in 1899 expressly for Sousa's band and its bell opened directly upward. The present bell-front type was first made in 1908." ["International Cyclopedia of Music," 1939]