Vanishment

Vanishment is the art of causing thing to vanish (making things go into non-being).

Nature
Vanishment is moderately difficult - learnt in Fourth Year and up - and is considered one of the hardest transfigurations to be tested on in one's O.W.L. and the difficulty of the vanishment to be performed positively correlates with the complexity of the organism to be vanished (for example, invertebrates are easier to Vanish than vertebrates)

Vanishing spells
Unlike conjuring spells, vanishing spells all follow the same formula of "X Evanesco", where X is the name of the object to be vanished and Evanesco is Latin for "disappear".