But even without a precise definition, its impact is being linked to health, workplace and mental issues, and researchers are taking note. A recent meta-analysis – a quantitative summary of the existing research into workaholism – by the University of Georgia showed, among other things, that workaholics are less productive than colleagues with a healthier attitude and approach to work.

Another large-scale study, published in May by the University of Bergen in Norway, linked workaholic tendencies to other psychiatric issues, like obsessive compulsive disorder, anxiety and depression.

Not your best work

But when does hard work turn negative? What might lead someone to believe they are a 'work addict'? Well, workaholism is a compulsion – an obsessive and out-of-control urge to work, or think about it, says Bryan Robinson, a psychotherapist based in North Carolina who conducted early research into the effects of work addiction and wrote Chained to the Desk, a guidebook for workaholics.

"Workaholism is not defined by hours. It's defined by what's going on inside of us,” he says.

“A workaholic is someone who's on the ski slopes dreaming about being back at work. A healthy worker is at work, dreaming about being on the ski slopes.”