If you think you might be a narcissist – or if you think your boss, best friend, or partner might be one – you could be right.

That said, you shouldn't go ahead and label them based on a hunch. Leave the diagnosis to a clinical professional.

Narcissism looks different in everyone, and varies in extremity. But psychologists and researchers have pinpointed a few key characteristics that apply to almost all narcissists.

They feel different from others

Craig Malkin, a lecturer at Harvard Medical School and the author of "Rethinking Narcissism," told Psychology Today that there are different types of narcissists.

For example, some are "communal," meaning they're so altruistic it's almost sickening. Others are "vulnerable," meaning they're sensitive to criticism and need constant reassurance.

But Malkin said all narcissists have "self-enhancement" in common: They somehow stand out from the pack.

Ultimately, it's a way of masking an unstable self-image. Eddie Brummelman, a developmental psychologist and a fellow at Stanford University, told Psychology Today that while narcissists feel superior to others, "they are not necessarily satisfied with themselves as a person."

They lack empathy

Joseph Burgo, a psychologist and the author of The Narcissist You Knowpreviously told Business Insider that the No. 1 sign of narcissism is an absence of interest in other people and an inability to feel for them.

For example, a narcissist might lose interest in group conversations when they're no longer about them, or feel completely indifferent when people talk to them about their emotions and issues they're struggling with. That makes it virtually impossible to develop a deep connection with anyone.

They need people to admire them

Psychotherapist Kathleen Schafler says one of the hallmark characteristics of narcissism is needing other people to ooh and aah over them.

Schafler wrote on Business Insider that a narcissist might "expect people to lose their cookies when they show up to an event or a party, and are often surprised or perplexed if people don't."

They care about status

Writing on Psychology Today, psychologist Elinor Greenberg says one of the "red flags" for Narcissistic Personality Disorder is status consciousness.

Greenberg writes:

"Narcissists make statements that show that they are extremely aware of status markers and frequently call attention to their own or other people's status.

They may make comments, such as: 'Do you know how rich he is?' 'Every important person in the city will be at that charity party. I have to be there or everyone will think I did not rate an invite.'"

They're too self-absorbed to listen to you

On Psychology Today, clinical psychologist Susan Heitler shares a short quiz to assess narcissism. (It's not a substitute for a clinical diagnosis.)

Heitler writes, "How well – or poorly – a person listens is a primary indicator of narcissism." In the assessment quiz, she asks readers to consider whether they identify with following behaviours including the following:

"What I want and what I have to say are all that matters when we talk together. When we make decisions what you want, your concerns, your feelings … these are mere whispers, inconveniences and irrelevancies."

This article was originally published by Business Insider.

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