Someone who thinks they are the best and are never wrong.

1) one who has become so ultimately consumed by their ego, that their entire view of the world and everyone in it is twisted. They usually perceive themselves as 'God's Gift to Women (mayhaps Men ...)' or are just plain sick as well as cocky.

2) A person whose ego exceeds both his intelligence and his capacity to see beyond his own personal interests.

3) A self-absorbed waste of oxygen who expects us to grovel at their feet like the unwashed masses they see us as

4) Someone who talks just to hear themselves (because no-one else will listen)

5) being egoist, is loving, respecting and admiring yourself more than any other being in the World. when you simply think, you're the best.
in better words: your egoist when you start feeling sorry for someone because you don't love him/her:)

Someone who think very highly of themselves and worries about their ego all the time.

stuck up.
not modest.
full of themselves.

The act of putting someone else down or insulting them to boost one's Ego. It is most commonly done through pointing out the other person's shortcomings.

Austin Clark

someone who would only have sex with themselves.