Meter is a term used by musicians to describe larger groups that repeat throughout a piece of music.
You might have sometimes tried to count along with a piece of music, for a lot of music you'll be able to this by counting 1, 2, 3 and 4 over and over again.
The reason this works is that the music is built on repeating patterns of four beats. When this is the case the music can be said to have a meter of 4. In this video we look at some other examples of music with a meter of 2 (meaning the music is split into two-beat groups) and 3 (meaning the music is divided up into three-beat groups).