Decanting is the act of slowly pouring liquid from its original container into a different one. It's a term that's often associated with wine, where the wine is poured from its bottle into a decanter or jug.

The main reasons for decanting wine are to remove any sediment that's formed in the bottle (it stays in the bottom of the bottle as the wine flows out), to let the wine 'breathe' and simply to make the wine look nicer, especially if you have a decorative decanter.