/ əˈkuːstɪk; NAmE / adjective ( NAmE also acous·tic·al / əˈkuːstɪkl; NAmE /)
1.
related to sound or to the sense of hearing
2.
[ usually before noun ] ( of a musical instrument or performance ) designed to make natural sound, not sound produced by electrical equipment
► acous·tic·al·ly / -kli; NAmE / adverb
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WORD ORIGIN
mid 17th cent.: from Greek akoustikos , from akouein hear.