'narcissism' - noun. The pursuit of gratification from vanity or egotistic admiration of one's own attributes. The term originated from Greek mythology, where the young Narcissus fell in love with his own image reflected in a pool of water.
So, we know exactly what it is, but how do you discover who suffers from it? Well, it's far simpler than you'd expect.
Psychology students have long used a 40-question diagnostic test to look for narcissism in a subject but, according to a new study based on 11 separate experiments, they really were overcomplicating things.
It turns out that all you really need to successfully identify a narcissist is one question:
'Are you a narcissist?'
And they'll answer yes. So long as they know what it means.
Brad Bushmna, professor of communication and psychology at The Ohio State University and a co-author of the study commented, "It's pretty cool actually, because narcissists aren't afraid to tell you they're narcissistic."
While it may seem obvious, it's worth bearing in mind that people tend not be honest with questions such as whether they indulge in casual sex or take drugs.
However, because they tend to lack empathy, they would have no problem declaring something that they would deem to be manifestly true, nor something they should be ashamed of.
Bushman explained that this 'one question' diagnostic test is not unique: "There are single item scales for other traits, like self-esteem for example. But the existing measure for narcissism is 40 items long."
He also explained why a test for narcissism is useful.
"It's an important personality dimension to measure. It's bad for the individual, because if you already think you're great you're not going to make any efforts to improve yourself. And it's bad for society as well, because if you're selfish you're less likely to be a cooperative and helpful member of your community."
Meanwhile - surprise, surprise - social media has amplified the issue in recent years - and it could be highly problematic.
"Social media is absolutely related to narcissistic behaviour. I've been studying aggression for about 30 years, and I've seen that the most harmful belief that a person can have is that they're superior to others... Men are better than women, my race is better than your race, my religion is superior to your religion. When people believe they're better than other people, they act accordingly. If people could believe that everyone on the planet is part of the same human family, and deserves the same respect, so many problems would be solved."
And Kanye might make better music again.