As nouns the difference between overconfidence and narcissism
is that overconfidence is an excessive degree of confidence while narcissism is excessive love of oneself.
overconfidence
English
Noun
(-)
An excessive degree of confidence
Related terms
*overconfident
narcissism
English
(narcissism)
Noun
(en-noun)
Excessive love of oneself.
Sexual desire for one's own body.
Derived terms
* narcissist
* narcissistic
*narcissize