Craic killer
Someone who spoils the fun. The opposite of good craic.
Don't invite him, he's a total craic killer, he'll have us home by ten.

Shall I translate it into posh English for you, mucker?
Ah, I was hoping you'd drop by. Here it is in posh English.
Do not invite him. He is an utter spoilsport and will have us home by ten o'clock.
Questions
What does craic killer mean in Ireland?
Someone who spoils the fun. The opposite of good craic.
How do you use craic killer in a sentence?
“Don't invite him, he's a total craic killer, he'll have us home by ten.”
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