The point of an area of study:
To interpret what it means to you.
So in saying this, you can still have a completely wrong answer. Although if you look at the definition, and tweak it a little to create your own definition that would be perfect.
Definition: the state of being accepted and comfortable in a place or group
I would tweak it this way.
Belonging is the way a person feels when being accepted into a place, group or home. It creates the feeling of acceptance, happiness and fulfilment. (Something, something, something)