5. (adj)harmonic of or relating to the branch of acoustics that studies the composition of musical sounds
"the sound of the resonating cavity cannot be the only determinant of the harmonic response"
6. (adj)harmonic, sympathetic relating to vibrations that occur as a result of vibrations in a nearby body "sympathetic vibration"
7. (adj)consonant, harmonic, harmonical, harmonized, harmonised involving or characterized by harmony