tilde power.
A tilde (from what I remember from school) is used in the "about" form. Like saying "He ate about four apples" but replacing "about" with "~" so you would say "He ate ~4 apples" or something like that. You don't know exactly how many apples he ate, so you're saying about. I could be wrong, but I'm pretty sure that's how my English teacher told us to use it.