beats per minute vs metronome marking

beats per minute and metronome marking both are nouns.

Word	Noun	Adjective	Verb	Adverb
beats per minute	Yes	No	No	No
metronome marking	Yes	No	No	No

As nouns, beats per minute and metronome marking are synonyms defined as:

beats per minute and metronome marking: the pace of music measured by the number of beats occurring in 60 seconds

Other synonyms of beats per minute include bpm, M.M..

beats per minute (noun)	metronome marking (noun)
the pace of music measured by the number of beats occurring in 60 seconds	the pace of music measured by the number of beats occurring in 60 seconds