"what's the craic" means: Classic Irish greeting that goes way beyond a simple 'what's up' — 'what's the craic' asks about the vibe, the gossip, the fun, and what's g.... There is a drug-related reference, so this is one worth noticing without overreacting. Many teens encounter such vocabulary through music, film and friends without any direct involvement. A neutral, curious conversation about where they heard the term and what they understand by it is far more useful than a confrontation. Watch for repeated context, not a single word.