It comes from the Greek word 'chero,' which means 'to rejoice.'
You know that feeling when something seems too good to be true — when it looks like a lot has happened in your favour recently, so it's suspicious?
Some people can't get over this feeling, and their good fortune takes a sinister turn in their mind.
People who have an irrational aversion to being happy suffer from something called "cherophobia." It comes from the Greek word "chairo," which means "I rejoice." It basically means that they are afraid to participate in anything fun.
It's not the activities that are scary, it's the fear that if you let go, and are happy and carefree, then something terrible will happen.
Cherophobia isn't widely-used or well-defined, and isn't in the latest edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-5), which is the main resource for diagnosing mental health conditions. But according to Healthline, some medical experts classify cherophobia as a form of anxiety.
Someone who has cherophobia probably isn't sad all the time, they simply avoid events and activities that could bring them happiness. Some symptoms of the disorder, according to Healthline, are:
In a blog post on Psychology Today, psychiatrist Carrie Barron discusses some possible reasons for people developing cherophobia, or "hedonophobia," which is defined as the fear of pleasure.
"There is so much talk about the pursuit of happiness these days," she wrote. "It might seem unusual for someone to fear this positive emotion. If it is due to a happiness/punishment link in childhood, it could be more common than we think."
For example, it could stem from the fear of conflict with a loved one, or a bad experience you associate with a certain event. If you're used to something bad happening straight after a happy event, you might resist going again.
"If you are pleasure averse, it may be because somewhere along the way, wrath, punishment, humiliation or theft – you earned it and they had to have it — killed your joy," Barron added. "Now you are afraid to feel it because the bubble burst/brutality is coming."
In an interview with The Metro news site, blogger Stephanie Yeboah described what it's like to live with cherophobia.
"Ultimately, it's a feeling of complete hopelessness, which leads to feeling anxious or wary of taking part in, or actively doing things, that promote happiness as you feel that it will not last," she said.
"A fear of happiness doesn't necessarily mean that one is constantly living in sadness. In my case, my cherophobia was exacerbated/triggered by traumatic events. Even things such as celebrating a campaign win, completing a difficult task or winning a client make me feel uneasy."
Treating cherophobia can sometimes be mistaken for treating feelings of depression, which Yeboah said isn't particularly helpful.
"There's not really much I can do as there aren't many resources that are specific for cherophobia, so I just kind of get on with it and try not to think about it where possible."
Barron said a good place to start is digging into your past, so you can try and learn to have tolerance for wasting time, having fun, and happiness without fearing negative consequences.
In particular, she said treatments like insight-oriented psychotherapy and cognitive behavioral therapy are useful for understanding the causes and undoing the negative associations people have between pleasure and pain.
Ultimately, tackling cherophobia is changing the way you think. If you think you may have it, it's likely a defence mechanism that you've put up, that was built because of a past conflict or trauma.
It will take time to work through your problems, but with treatment, you may be able to get past it, enjoy happiness, and start living in the moment.