You hear the term narcissist tossed out frequently, but is that date who’s more interested in hearing himself talk really a narcissist or just a jerk? What about your boss who always demands you do things his way? The term stems from the Greek myth of Narcissus, a beautiful and proud young man who was cursed by the god Nemesis to fall in love with his own reflection and died pining for his own beauty. But in real life, psychologists have developed a list of actual criteria for the definition of narcissism.

Narcissistic Personality Disorder (NPD), as it’s called in the Diagnostic and Statistical Manual of Mental Disorders (DSM), “is one of the least understood of personality disorders,” psychologist Anjhula Mya Singh Bais tells mental_floss. A former model and now Ph.D, Bais has for the past 10 years worked with clients who are celebrities, high achievers, and their partners dealing with various facets of NPD.

Bais says the NPD diagnosis evolved through collaboration between psychoanalysts and psychologists over the years “who couldn’t quite put their finger on a subset of their patients." NPD also tends to co-exist with depression or anxiety; having one of those conditions is often the only reason a narcissist tries therapy.

To qualify as a narcissist, an individual must have "a pervasive pattern of grandiosity (in fantasy or behavior), need for admiration, and lack of empathy, beginning by early adulthood and present in a variety of contexts," paraphrased from the fifth version of the DSM [PDF]:

— A grandiose sense of self-importance, exaggerating achievements and talents

— Fantasizes about unlimited success, power, brilliance, beauty, or ideal love

— Believes that he or she is “special” and should associate only with high-status people or institutions

— Requires excessive admiration

— Has a sense of entitlement, expects favorable treatment or automatic compliance

— Is interpersonally exploitative, taking advantage of others

— Lacks empathy, unwilling to recognize or identify others' feelings and needs

1. NARCISSISTS LIVE IN A GRANDIOSE WORLD OF THEIR OWN MAKING.

Narcissists become fixated on fantasies of infinite success, control, brilliance, beauty, or idyllic love, Bais says. They believe they are "extraordinary and exceptional and can only be understood by, or should connect with, other extraordinary or important people or institutions.”

2. NARCISSISTS DO NOT EXPERIENCE EMPATHY.

What makes narcissists incredibly difficult to be in relationship with is “they lack empathy in totality,” Bais says. They do not care about others’ points of view or feelings, unless “it is to manipulate a situation or person to their advantage,” she adds. Psychologist Brad Reedy, the clinical director of Evoke Therapy Programs, puts it more bluntly. “If you don’t fulfill their needs, they have no use for you,” say Reedy, who has treated clients with narcissism in therapy for 20 years. In this regard, the difference between a narcissist and a sociopath—who also views people as objects and lacks empathy—may simply be a matter of degree.

3. YET THEY HAVE A MADDENING ABILITY TO CHARM.

A romantic relationship with a narcissist may start with passion and excitement. Your narcissist may be the most dynamic person in the room or “extraordinarily charming,” Bais says. But that charm eventually gives way to manipulation, entitlement, lack of forgiveness, a desperate need for ego strokes, and even rage.

4. NARCISSISM IS WORSE THAN ARROGANCE.

According to Reedy, the narcissist’s personality is so pervasive, rigid, and consistent that “they won’t be able to demonstrate anything different than the narcissist presentation.” A person who is just a little arrogant still has moments where they can admit they’re wrong, apologize for their mistakes, and empathize. But unlike people with “strong confidence” or arrogance, narcissists “place value only on [themselves] and no one else,” Bais says.

5. NARCISSISM STARTS IN CHILDHOOD …

Narcissism is forged by “a fundamental lack of connection in childhood—a lack of attachment,” Reedy explains. This “narcissistic wound,” as psychologists call it, comes from what Reedy describes as “valuing the wrong thing in the child”—such as praising them for their achievements or outward appearance, but never for their inner value. In this way they differ from people with anti-social personality disorder, who usually have experienced direct abuse. Many children who become narcissists, according to psychologist Alice Miller’s landmark book The Drama of the Gifted Child, consistently seek admiration because of an empty sense of themselves. Without therapy, Reedy says, “it is impossible for the grandiose person to cut the tragic link between admiration and love.”

6. … BUT CAN ONLY BE DIAGNOSED IN ADULTHOOD.

Be careful not to call your child or teen a narcissist, Reedy cautions. “Developmentally, children have many narcissistic traits," he says. "This is normal. Shaming them is not healthy.”

7. TRY NOT TO TAKE A NARCISSIST’S BEHAVIOR PERSONALLY.

Since narcissists require immense amounts of therapy to even begin to make changes in their nature, your best bet if you’re dealing with one in your life, says Reedy, is to “see them for what they are and don’t take it personally. It really isn’t about you.” However, narcissists inspire in others an understandable urge to “take them down a notch” or “put them in their place," Reedy says, which will only further aggravate a narcissist’s behavior. “A superiority complex always covers up an inferiority complex.”

8. HOWEVER, YOU MIGHT HAVE TO LEAVE A RELATIONSHIP WITH A NARCISSIST.

Since narcissists are unlikely to change on their own without therapy—which most of them are unlikely to seek out unless they have co-existing anxiety or depression—you may have to accept that the only solution for a healthy relationship is to leave. “If that is either impractical or you are unwilling to leave [the relationship], be sure not to try to fix it or conclude that you can fix it if you do all the right things,” Reedy advises. He considers that the most common mistake of people who stay in “toxic relationships.”

9. THERAPY MAY HELP NARCISSISTS TO CHANGE.

The cure is long-term therapy, Reedy says, “where one experiences something different than what they experienced in their childhood.” However, getting a narcissist to therapy is no small task, as many of them view therapy as an admission of something wrong with them. The good news is that once they’re getting help, Bais says, they do respond well to psychotherapy.