adj. also a·cous·ti·cal (-stĭ-kəl)
1. Of or relating to sound, the sense of hearing, or the science of sound.
a. Designed to carry sound or to aid in hearing.
b. Designed to absorb or control sound: acoustic tile.
a. Of or being an instrument that does not produce or enhance sound electronically: an acoustic guitar; an acoustic bass.
b. Being a performance that features such instruments: opened the show with an acoustic set.
An acoustic instrument.
[Greek akoustikos, pertaining to hearing, from akouein, to hear; see kous- in the Appendix of Indo-European roots.]
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