That's an interesting question with no very good answer. The sea has a complex terminology all its own, and the more you get into it the richer and more complicated it gets. I think I'm just going to cheat and consult a dictionary. Otherwise I will just get tangled up trying to remember the differences between pinnaces, yawls, schooners, dinghies, cutters, ketches, and Chesapeake skipjacks. ahdictionary.org says that a boat is a. A relatively small, usually open craft of a size that might be carried aboard a ship. b. An inland vessel of any size. c. A ship or submarine. According to (c), "boat" CAN mean "ship," which makes perfect sense. The "ferryboat" we took across Lake Michigan was the S. S. Badger, a 125-meter, 4000-ton coal-burning steamship, complete with staterooms. I learned something today, because the idea that a boat means something that "might be carried ABOARD a ship" was something I didn't know, but it makes sense. Again according to the dictionary, a "ship" is a. A vessel of considerable size for deep-water navigation. b. A sailing vessel having three or more square-rigged masts.

The difference between a ship and a boat is size. Generally, a boat is a smaller craft than a ship. "Ship" is the more broad term for any oceangoing craft. A boat is a small vehicle for travelling (traveling) on water. A boat can have oars, paddles, sails, or a motor to make it move. A ship is a large boat that can travel across deep water, such as a sea or ocean. A ship is built to carry people or goods for a long distance. A ship is propelled by sail or power only. However, there are two notable exceptions: submarines are officially boats and ore-carrying vessels that traverse large lakes are also called "boats". Source: http://dictionary.reference.com/help/faq/language/d18.html See also: - http://www.vocabulary.com/dictionary/boat

galleys?