"Craic" in Ireland

"Craic" is an Irish word of broad ideomatic use in Irish English.

On its own, the word means "fun" — easy good times, traditionally at a pub in the evening.

"What's the craic" means "How're you doing."

"How was the craic" inquires about a social experience.

"Great craic" describes an occasion.

"The craic was 90" is the superlative, apparently. There's a song about it. Nobody knows what it means.