What is commonly referred to as a "doghouse" on an aircraft?

The term "doghouse" commonly refers to a storage area on an aircraft designated for supplies and emergency equipment. This area is crucial for flight attendants as it houses essential items needed to ensure passenger safety and comfort during the flight. The doghouse typically contains first aid kits, emergency equipment, and other supplies necessary to respond to in-flight needs, making it an integral aspect of the cabin's operational readiness.

In contrast to this, the other options describe different aspects of the aircraft. A passenger seating area is primarily for passengers to sit during the flight, while bathroom facilities are designated for passenger use and personal hygiene. An area for crew rest is specifically set up for cabin crew to take breaks and rest between duty periods but does not function as a storage location.