sone
/soʊn/
noun
- A unit used to measure the perceived loudness of a sound. One sone is equal to the loudness of a 1,000-hertz tone at 40 decibels above a listener's threshold of hearing.
- A quiet library might measure less than 2 sones.
- The new fan operates at only 1.5 sones, making it almost silent.
- The vacuum cleaner was rated at about 8 sones, which is quite loud.