noun
a noun is a word that represents a person, place, thing, or idea. In this case, 'improvisation' is a noun that refers to the act of improvising or creating something without preparation or planning.
The musician's improvisation during the concert was truly impressive.
I love watching comedians do improvisation on stage.
The actor totally nailed the improvisation in that scene.
Life is like a constant improvisation, you never know what's coming next.