Pronunciation: (u-kOO'stiks), [key]
1. (used with a sing. v.) Physics.the branch of physics that deals with sound and sound waves.
2. (used with a pl. v.) the qualities or characteristics of a room, auditorium, stadium, etc., that determine the audibility or fidelity of sounds in it.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.