Hygge was never meant to be translated - it was meant to be felt
Sitting by the fire on a cold night, wearing a woolly jumper, while drinking mulled wine and stroking a dog - probably surrounded by candles. That's definitely "hygge".
Eating home-made cinnamon pastries.
Watching TV under a duvet.
Tea served in a china set.
Family get-togethers at Christmas.
They're all hygge too.
The Danish word, pronounced "hoo-ga" Danish, hygge (pronounced “HUE-gah”), is usually translated into English as "cosiness". But it's much more than that, say its aficionados - an entire attitude to life that helps Denmark to vie with Switzerland and Iceland to be the world's happiest country.
With as little as four sunshine hours a day in the depths of winter, and average temperatures hovering around 0C, people spend more time indoors as a result, says Nilsson, meaning there's greater focus on home entertaining:
"Hygge could be families and friends getting together for a meal, with the lighting dimmed, or it could be time spent on your own reading a good book. It works best when there's not too large an empty space around the person or people."
The idea is to relax and feel as at-home as possible, forgetting life's worries.
"The rest of the world seems to be slowly waking up to what Danes have been wise to for generations - that having a relaxed, cosy time with friends and family, often with coffee, cake or beer, can be good for the soul," says Helen Russell, author of The Year of Living Danishly: Uncovering the Secrets of the World's Happiest Country.
"Hygge seems to me to be about being kind to yourself - indulging, having a nice time, not punishing or denying yourself anything. All very useful come January when in the UK everyone's on diets or manically exercising or abstaining from alcohol.
The adjectival form of hygge is "hyggeligt", a word offered as a compliment to a host after a pleasant evening at their home.
"Hygge isn't just a middle-class thing. Absolutely everyone's at it from my dustbin man to the mayor," says Russell. "Hygge is so crucial to living Danishly that the other day on the motorway, I saw a camper van driving along with lit candles in the windows. This is probably illegal but Vikings don't tend to be too hung up on health and safety.
Origin of 'Hygge'
• Term comes from a Norwegian word meaning "wellbeing"
• First appeared in Danish writing in the 19th Century and has since evolved into the cultural idea known in Denmark today
"It's interesting that the word doesn't really translate into other languages. Hygge isn't restricted to Denmark, so why is it so hard to describe without borrowing a Danish word?"
It sounds a bit like the English word "hug", for which the Oxford English Dictionary lists no origins. The 19th/early 20th Century philologist Walter William Skeat thought it might be of Scandinavian origin. Notionally the effect of hygge and a hug is similar - comforting and secure. An obsolete meaning of hug is "to cherish oneself; to keep or make oneself snug", according to the OED.
Sometimes you see or do things that you would call 'hyggeligt' in the UK but you wouldn't use that word to describe them because people wouldn't know what you're talking about.
Some older Danes feel that hygge isn't what it used to be, as the stress on socialising has lessened. It's now generally considered hyggeligt to watch TV alone or watching a DVD set, perhaps while eating crisps.
Other countries and cultures have similar expressions. In German there's Gemutlichkeit, a sense of wellbeing based on good food, company and perhaps a drink. But Danes insist hygge is unique.
The blogger Anna Lea West, has offered "cosiness of the soul" as an English definition.
"Hygge was never meant to be translated. It was meant to be felt," translator ToveMaren Stakkestad has written. Maybe the only way to understand this slippery cultural idea is to visit Denmark, rather than read about it.
"It's an idea so rooted in the Danish sense of togetherness, and perhaps even in Denmark's social democracy, that a Brit might struggle to grasp its historic and social significance," says Patrick Kingsley, author of the travel book How To Be Danish.
"But that said, in essence hygge is about a group of slightly gloomy friends huddling under the duvet on a cold winter's night."