(1) Any master tape of one song, whether recorded for inclusion in an album, or as the A- or B-SB side of a single. Always capitalized, Side is used in recording contracts, so precise definition is important.
(2) In the AFTRA Code of Fair Practice, a Side is a master tape of no more than 3 1/2 minutes. If the total length of the song is longer than that, AFTRA singers receive additional payment.