A false keel, also known as a centerboard or a daggerboard, is a type of underwater appendage that helps sailboats remain stable and steady in the water. It functions as an additional keel, which usually swings or slides out from the hull's centerline when needed. A false keel is an essential feature for boats that need to sail in shallow waters or navigate through narrow passages. Other synonyms for false keel include fin keel, wing keel, and bulb keel, each with slight variations in design and function. Overall, having a strong and reliable false keel is crucial for maximizing the performance and safety of your sailboat.