A musical composition in three movements, with two sets of instruments, one larger than the other. Typically a concerto has a solo instrument play with an orchestra.
Examples of concertos are Bach's Italian Concerto in F major (for Harpsichord) and Elgar's Cello Concerto in E minor.
Sir Edward Elgar (1857-1934) was a composer of classical music. His most famous compositions include his Cello Concerto in E minor, and the six Pomp and Circumstance Marches (the first of which is played at most graduation ceremonies).
"They're going to play Elgar's Pomp and Circumstance March No. 1 at my graduation ceremony."