The term BIG BOAT can refer to several different types of vessels. The three-letter word ARK is a reference to the large boat built by Noah in the Bible, which was used to save two of every animal from the Great Flood. A YACHT is a five-letter word that typically refers to a recreational vessel, usually used for pleasure cruising or racing. A LINER is also a five-letter word and is a type of large passenger ship, often used for transoceanic voyages. Finally, NOAH is a four-letter word that is a reference to the Biblical figure who built the ARK.