S: (n) equal temperament (the division of the scale based on an octave that is divided into twelve exactly equal semitones) "equal temperament is the system commonly used in keyboard instruments"
S: (n) calibration, standardization, standardisation (the act of checking or adjusting (by comparison with a standard) the accuracy of a measuring instrument) "the thermometer needed calibration"
S: (n) activity (any specific behavior) "they avoided all recreational activity"