concert (a musical entertainment in which several voices or instruments take part)

rhythm game (genre of video game)

(music) classical music

musicology

light music (such as popular songs, jazz, chanson, etc.), as opposed to classical music / semiclassical music

band (almost always a brass band formed from members of bodies such as the military or police)

perfectionism

(computing theory) Turing complete

(number theory) perfect number, a positive integer that is equal to the sum of its positive divisors, excluding the number itself

perfect and without blemish; flawless