A children's card game, sometimes played with a special deck, where the object of the game is for each player to find matches for all the cards in his hand, without being stuck with the single unmatchable card.
The unmatchable card itself.
A spell (now rare but still found in compounds such as hex sign and hexcraft).
A hexagonal space on a game board.
An evil spell or curse.
A witch.
a hexagon-shaped item of rock climbing equipment intended to be wedged into a crack or other opening in the rock.
To cast a spell on (specifically an evil spell), to bewitch.