“Egotism” is an inflated sense of one’s importance; it’s being conceited or vain.
1a: excessive use of the first person singular personal pronoun 1b: the practice of talking about oneself too much 2: an exaggerated sense of self-importance
The egotist feels superior to others physically, intellectually or in some other way.
“Egoism” is a preoccupation with oneself, but not necessarily feeling superior to others.
1a: a doctrine that individual self-interest is the actual motive of all conscious action
1b: a doctrine that individual self-interest is the valid end of all actions
2: excessive concern for oneself with or without exaggerated feelings of self-importance
The egoist puts themselves and their own needs before everyone else’s.
Egotist: I’m the smartest, prettiest and most talented.
Egoist: It’s all about me regardless of how I compare to everyone else.