(1) In general, that part of physics which concerns itself with sound - its causes, characteristics, and effects. In surveying, acoustics is involved primarily in the development and use of sub-marine surveying by sonar and analysis and use of natural and artificially-caused seismic events.

(2) In particular, that part of architecture which concerns itself with the design of buildings where the relation of the design to the quality or amount of sound in it is of first importance.