We have Greek mythology to thank for the origin of the term 'narcissism.' As described in Personality Disorders in Modern Life, Narcissus was a beautiful and well-loved young man who was unable to love anyone in return. Upon seeing his reflection in a pool of water, he fell in love with himself. But because Narcissus did not realize he was gazing at his own reflection, he drowned in an attempt to get closer to the only one he loved.
The term 'narcissism' first entered the world of psychiatry in 1889. Sigmond Freud later published On Narcissism in 1914. Given how long the word has been around, perhaps it's no surprise that it's getting a little tired.