Cadenza

In music, a cadenza (from Italian: cadenza, meaning cadence; plural, cadenze) is, generically, an improvised or written-out ornamental passage played or sung by a soloist or soloists, usually in a "free" rhythmic style, and often allowing for virtuosic display. Indicated by a fermata in all parts if improvised, a cadenza is usually over a final or penultimate note in a piece or important cadence and the accompaniment rests or sustains a note or chord. Thus it is often before a final coda or ritornello.

Read more about Cadenza:  In Concerti, As A Vocal Flourish, In Jazz, Notable Examples of Cadenzas