'Egotism' definitions:

Definition of 'egotism'

noun

An exaggerated opinion of your own importance [syn: egotism, self-importance, swelled head]

noun

An inflated feeling of pride in your superiority to others [syn: ego, egotism, self-importance]

From: GCIDE

Egotism \E"go*tism\ (?; 277), n. [L. ego I + ending -tism for -ism, prob. influenced by other English words in -tism fr. the Greek, where t is not part of the ending, as baptism. See Egoism.] The practice of too frequently using the word I; hence, a speaking or writing overmuch of one's self; self-exaltation; self-praise; the act or practice of magnifying one's self or parading one's own doings. The word is also used in the sense of egoism. [1913 Webster]
His excessive egotism, which filled all objects with himself. --Hazlitt.
Syn: Egotism, Self-conceit, Vanity, Egoism. Self-conceit is an overweening opinion of one's talents, capacity, attractions, etc.; egotism is the acting out of self-conceit, or self-importance, in words and exterior conduct; vanity is inflation of mind arising from the idea of being thought highly of by others. It shows itself by its eagerness to catch the notice of others. Egoism is a state in which the feelings are concentrated on one's self. Its expression is egotism. [1913 Webster]