Definition and background:
An ensemble of musicians that specialize in jazz music of the " Swing Era" of the 1930's and 1940's. After World War II (1945), the popularity of swing dancing subsided shifting the focus from dances to concerts. The size and instrumentation of the ensemble can range from a small group of about twelve performers to an entire big band or jazz orchestra with twenty or more. Vocalists are often part of the big band. The modern big band typically includes:WOODWINDSBRASSRHYTHM SECTION2 - Alto Saxophones2 - Tenor Saxophones1 - Baritone Saxophone5 - Trumpets(Flugelhorns)5 - Trombones1 - Electric Guitar1 - Piano1 - String Bass1 - Drum KitFlute *BbClarinet *Bass Clarinet *Soprano Saxophone *Bass Saxophone *Horns *Tuba *Vibraphone *Marimba *Unpitched Percussion ** This is an instrument not always found in a typical big band. Occasionally parts are written for these instruments and the large amateur or professional band will try to be faithful to the composer's wishes.
For more information on the music term "Big band" check out these other resources:
Wikipedia - Glossary of Musical Terminology
Virginia Tech Multimedia Music Dictionary
ORB -- Medieval Music Glossary