An Etymological Dictionary of Astronomy and Astrophysics

1. The study of sound, especially of its generation, propagation, and reception.
   
2. Those qualities of an enclosure that together determine its character with respect to distinct hearing.

Etymology (EN): From Fr. acoustique, from Gk. akoustikos “pertaining to hearing,” from akoustos “heard, audible,” from akouein “to hear,” from copulative prefix a- + koein “to mark, perceive, hear,” from PIE root *(s)keu- “to notice, observe.”

Etymology (PE): Sedâyik from sedâ “sound” + Pers. suffix -ik, → -ics. Sedâ is most probably Persian,
since it exists also in Indo-Aryan languages: Skt. (late Vedic): sabda “articulate sound, noise,”
Pali and Prakriti: sadda “sound, noise,” Sindhi: sadu, sado “shout, call,” Gujrâti sad “call, voice, echo,” Marathi: sad “shouting to,” Konkani sad “sound,” Sinhali: sada “sound.” Therefore, sadâ in Arabic “reverbrating noise, echo” may be borrowed from Persian, or a coincidence. Note that for the author of the classical Persian dictionary Borhân-e Qâte’ (India, 1652 A.D.), the Arabic term is a loanword from Persian.

See also: → phone; →phonetics.