1) An amount due; a debt.
2) A grievance that is harbored and requires satisfaction
3) A group of 20 items.
4) The act of securing an advantage, especially a surprising or significant gain.
5) The act or an instance of buying illicit drugs.
6) A successful robbery.
7) A sexual conquest.
1) "that guy owes me a score."
2) "settle an old score."
4) “He had dropped out of school and gone for that quick dollar, that big score” (Peter Goldman).
In film; A score is the music that aids the film usually made up of orchestra music (violins, Drums, Horns, Chellos, Piano, etc). Typically these scores, also called soundtracks in many cases (as they go to film and television) are styled classically but with a modern twist.
Hans Zimmer does the score for the films Lion King, Pirates of the Caribbean 2, 3, and 4, The Simpsons Movie, and The Batman Trilogy (Batman Begins, The Dark Knight, and The Dark Knight Rises).