It is an exclaimation of personal victory in aspects such as video games and rock, paper, scissors battles. Sometime accompanied with a gesture that goes: clap, snap fingers and point upwards as if towards the heavens.
its a cooler way of saying shoot. its sorta like shoot and hoot smashed together to create shahoot. when you say shahoot, it makes you feel cooler, espesh when you add in a sick hand gesture or funny face. When things are really intense though, you can switch it up to shithoot mayne. & the mayne part of it just makes it sound ten times cooler. Also you can add an excessive number of "o's" to shahoooooot to make it look sick. ya get mah flow brah?
Shahoooot, I just failed my gov test, awhh shahoot mayne, that sucks.