beats per minute

Beats per minute (BPM) is a unit typically used as either a measure of tempo in music, or a measure of one's heart rate. A rate of 60 bpm means that one beat will occur every second. One bpm is equal to 1/60 Hz.The BPM tempo of a piece of music is conventionally shown in its score as a metronome mark: This indicates that there should be 120 crochet beats (quarter notes) per minute. In simple time signatures it is conventional to show the tempo in terms of the note duration on the bottom. So a 4/4 would show a crochet (or quarter note), as above, while a 2/2 would show a minim (or half note).
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Noun
1. the pace of music measured by the number of beats occurring in 60 seconds
(synonym) bpm, metronome marking, M.M.
(hypernym) pace, gait
(part-holonym) music
(classification) music