what does FAlSETOO from the?

When you speak or sing you have your normal tone and can change your tone to usually one octave higher or lower. Changing the tone of your voice higher is called your faisetoo.

The term falsetto (Italian diminutive of falso, false) refers to the vocal register occupying the frequency range just above the modal voice register and overlapping with it by approximately one octave. It is produced by the vibration of the ligamentous edges of the vocal cords, in whole or in part. Though frequently used in reference to a particular type of vocal production in singing, falsetto vocal production also occurs within speech and is one of the four main vocal registers identified within speech pathology. The characteristic sound of falsetto is inherently breathy and flute-like, with few overtones present. The falsetto voice is more limited in dynamic variation and tone quality than the modal voice in both speaking and singing. Both men and women can phonate in the falsetto register.[1] The term falsetto is most often used in the context of singing to refer to a vocal technique that enables the singer to sing notes beyond the vocal range of the normal or modal voice.[2]

It's a word for when you bring your voice up really high, similar to opera music.

It means that your voice is extremely high...