submarina

Submarina is a term used in several Romance languages to denote a submarine, a watercraft capable of independent operation underwater. A submarine is designed to travel submerged for extended periods, sometimes for reconnaissance, combat, or research. Modern submarines combine a pressure hull, ballast tanks, and propulsion systems that allow controlled diving, cruising, and surfacing. They may rely on diesel-electric propulsion with battery reserves or nuclear power, enabling longer endurance without surfacing.

Ballast tanks take in and expel water to change buoyancy, while the hull supports pressure at depth. Submarines use sonar and periscopes for navigation when near the surface and hydrodynamic shapes to minimize drag. Onboard life-support systems provide air, water, and waste handling for the crew, with stealth considerations such as reduced sound signatures and quieting technologies. Armament or scientific payloads vary by class, from torpedoes and missiles to scientific instruments.

Submarines have a long history of development, with early experiments in the 17th to 19th centuries and heavier usage in the 20th century. The first practical military submarines emerged in the 1860s–1880s, with rapid advances in propulsion, hull design, and sensors through World War II and the Cold War. Today, submarine fleets include attack submarines for offensive operations, ballistic missile submarines for strategic deterrence, and research or civilian submarines used for oceanography, exploration, or salvage. The term “submarina” remains common in some languages, but in English the vehicle is generally called a submarine.