A funnel is the smokestack or chimney on a ship used to expel boiler steam and smoke or engine exhaust. They are also commonly referred to as stacks.

The tall, often distinctively shaped structure on top of a cruise ship is the Funnel (or smokestack). Its primary purpose is to exhaust combustion gases from the ship's massive engines and generators high into the air, away from the passenger decks. While modern ships have advanced filtration systems, the funnel remains an essential engineering component. Beyond its function, the funnel is the visual "signature" of a cruise line. For example, Carnival Cruise Line is famous for its "Whale Tail" funnel, while Disney Cruise Line features iconic red funnels with Mickey silhouettes (often one is "fake" and used for storage or a kids' club). Near the funnel, you will also see the Radomes—those large, white, ball-shaped domes. These protect sensitive satellite and radar antennas from the wind and salt spray, allowing for the ship's GPS navigation, weather monitoring, and the high-speed Starlink Wi-Fi that passengers use in 2026.