Akademik

a musical notation indicating the number of beats to a measure and kind of note that takes a beat

noun, pl ⋯ -tures [count]

: a number that is written at the beginning of a piece of music and that shows the number and length of the beats in each measure

ˈtime signature [time signature] noun (music)

a sign at the start of a piece of music, usually in the form of numbers, showing the number of beats in each ↑bar