"Knuckle" refers to the joint in the human finger where two bones meet. It is commonly associated with the bony protrusions that can be seen when a fist is made. The knuckles play a crucial role in hand movement and dexterity, allowing for gripping and manipulation of objects. In addition to its anatomical meaning, "Knuckle" can also refer to a type of game or sport, such as knucklebones, which involves tossing small objects and trying to land them in a specific way. This game has historical roots and has been played in various cultures around the world.