The word bluff is from the Dutch word bluffen, meaning to deceive, and entered English as a nautical reference to the imposing front of a warship.
For the same reason, the term bluff was applied to a bold coastline that rose straight and high out of the water.
By the 1830s, bluffing had taken on the meaning of anything less intimidating than it appears and had entered the game of poker as a reference to the art of deception.
A poker player, or anyone putting up a false front, is “bluffing”.
