Meditation is simply focusing on a thing.
It can be your breath to calm down, a situation or emotions to better understand/accept them.
The warmth of the sun or the feeling of a breeze so as to enjoy/appreciate nature.
You can also meditate simply on your body, in which case depending on how you do it it be closer to Tai Chi.
And yes music and movement can be part of it.
It is what you make of it, though if you are someone prone to or already depression/depressed you need to watch out.
Since focusing on emotion can then become a double edge'd sword, though it can also help.