Putting powder in some kind barrier like a tissue and swallowing it, but some people also use the term to just mean swallowing some powder straight, no bread or dip. I'm thinking I shouldnt even answer this so that it just fades away as this is basically the easiest question to look up.
it means to put powder into a rolling paper (usually) and wrap it up, so you can swallow it without tasting the product, for example MDMA tastes nasty... so you wrap it up, and the rolling paper will dissolve very quickly in your stomache