Overweening (adjective)

Excessively conceited or arrogant; having or showing an exaggerated sense of self-importance.

Origin:

Late middle english, from overween + -ing.

Examples:

1. He had an overweening sense of self-importance.
2. She had an overweening belief in her own abilities.
3. They had an overweening desire to be the center of attention.
4. I had an overweening need to be in control.
5. You have an overweening attitude and it's hard to work with you.