chess

(noun): A game that's easy to learn but impossible to master, causing losers to hate it and winners to lord their superiority over everyone else. Just don't knock over the pieces in a fit of rage.

(n.) a board game derived from earlier antecedents in Persia or China, in which players must use lesser pieces to successfully capture the enemy king

considered a good way to teach tactical thinking, presumably for some upcoming war where both sides politely take turns, held entirely on a featureless flat plane