Aboard ship, naval personnel eat in the:

Naval personnel eat aboard ships in the messdeck, which is specifically designed for sailors to gather for meals and social interaction. The messdeck serves a functional purpose, providing a dedicated space for dining and fostering camaraderie among crew members. This term is uniquely associated with naval environments and reflects naval customs and traditions.

While the galley refers to the kitchen or food preparation area where meals are cooked and prepared, and a dining room generally refers to a regular household setting where meals are consumed, the messdeck is a distinct feature of naval vessels that combines both dining and community aspects for the crew. Cafeteria is a term often used in civilian contexts and does not capture the naval setting or traditions associated with dining on a ship.