We've been saying it for years, without fully understanding it.
When there's a house party that empties out in the small hours of the morning, 'The craic was 90.'
When it's just a handful of people sitting around watching bad TV, 'The craic was 90,' can be uttered, dripping in sarcasm.
Weddings, birthdays, after-work drinks - the craic can be 90 at them all, but what does this even mean and where did it come from?!
Lads, where does the phrase 'The craic was 90' come from??! @MuireannO_C wants to know pic.twitter.com/TYZKy7gtND
— Today FM (@todayfm) April 10, 2017
Some people believe the craic is 90 because we could never reach the full capacity craic of 100, "If u say the craic is 100 that means it can't get any better. When we all know things can always get better."
While others think it's a reference to 90 miles an hour, because "everything in Ireland is 90 miles an hour!"
Maybe it's a reference to Italia '90 and the almighty craic that was had that summer?
Or perhaps the legend that is Christy Moore is responsible for the Irish saying with 'The Craic was 90 in the Isle of Man.'
Either way it's a champion of a phrase we'll be using for years to come!