The word narcissism comes from the Greek myth of Narcissus, an attractive young man who set out looking for someone to love. The beautiful nymph Echo falls in love with him and repeats everything Narcissus says, but he rejects her and she fades away. Narcissus keeps looking for the perfect mate until one day he sees his own reflection in the water. Narcissus falls in love with his own image and gazes at it until he dies. At that spot on the riverbank grew the flower now known as the narcissus (a sub-species of daffodil). The myth of Narcissus captures the tragedy of self-admiration, because Narcissus becomes frozen by his self-admiration and unable to connect with anyone outside of himself—and his narcissism harms other people (in this case, Echo).
From the book The Narcissism Epidemic
More on the story of Echo and Narcissus