from Wiktionary, Creative Commons Attribution/Share-Alike License
- n. An instrument for measuring sounds.
from the GNU version of the Collaborative International Dictionary of English
- n. An instrument for measuring sounds, as to their intensity, or the frequency of the vibrations.
from The Century Dictionary and Cyclopedia
- n. An instrument for experimentally determining and exhibiting the number of vibrations of a sonorous body (as a string or tuning-fork) in a unit of time.
- n. In psychophysics, an instrument for the production of accurately graded intensities of sound. The simplest form of phonometer is the sound-pendulum (which see). In Wundt's gravity-phonometer, ivory balls are dropped by electromagnetic releases from varying heights upon hard-wood plates.
- n. A clockwork instrument swung in gimbals, so that its face is always horizontal, and on whose dial are certain marks indicating intervals at which a whistle or other signal should be made to announce the compass course of the vessel.
phono- + -meter (Wiktionary)