Rubato is a musical term that refers to tempo fluctuations, where the performer may speed up or slow down the tempo at their discretion for expressive purposes.

The acronym OPTEMPO is a military term (operations tempo).

The common musical term is "up-tempo" (faster tempo, as in jazz).

up tempo

I think most people would say "Wrecking Ball" is a medium up-tempo pop song. In other words, it starts in a medium tempo and then when she reaches the chorus, she switches to a more up-tempo sound.

(Music)

The tempo of the concerto is too slow for the average listener.

(Speed)

The war increased the tempo of manufacturing operations in the country.

(Slang)

We are putting up a tempo this year. (Temporary plastic carport)