Sylabex is a word-making game, easy to play in which both skill and luck are involved.

The cards all bear a three-letter syllable and a number (which is the points value used in scoring). Any cards when placed beside certain of the other cards forms a complete six letter word, or in some cases will form a nine letter word.

The object of the game is to make words with all the cards in your hand. Other players score the points value of the cards in hand when the round ends, and the winner is the player with the lowest score after the agreed numbers of rounds.

The first Pepys edition had 72 cards, including four wildcards which can represent any three letters the player chooses. The second edition was shrunk to 44 cards and sold in a smaller box as a game for 2-5 players. Both versions include rules for playing as a solo patience game.