conceited

A conceited person has an inflated self-image and perceives himself as incredibly entertaining and wonderful. Talk incessantly about your accomplishments on the clarinet or amazing ability to wiggle your ears, and people are going to think you’re conceited.

An offshoot of conceit, conceited was first recorded in 1600 as meaning “having an overwhelming opinion of oneself.” It’s a shortened form of “self-conceited” and the total opposite of "modest." In a remark about such vain people, the English Victorian novelist George Eliot once said, “I've never any pity for conceited people, because I think they carry their comfort about with them.”