Cooler

general

A hand where two players have very strong holdings — unavoidable losses happen.

AA vs KK preflop is the textbook cooler. Set-over-set, top-set vs nut flush — these are losses that aren’t leaks; they’re variance.

See also

Action
Your turn to act, or the overall betting activity in a hand.
Bad Beat
Losing a hand where you were a heavy statistical favorite.
Board
The community cards dealt face-up in the middle of the table.
Fish
A weak, losing player.