trimaran

thumb|USA 17 (yacht)|USA-17—a trimaran, type BOR90. thumb|A traditional paraw double-outrigger sailboat (bangka) from the Philippines A trimaran (or double-outrigger) is a multihull boat that comprises a main hull and two smaller outrigger hulls (or "floats") which are attached to the main hull with lateral beams. Most modern trimarans are sailing yachts designed for recreation or racing; others are ferries or warships. They originated from the traditional double-outrigger hulls of the Austronesian cultures of Maritime Southeast Asia; particularly in the Philippines and Eastern Indonesia, where it remains the dominant hull design of traditional fishing boats. Double-outriggers are derived from the older catamaran and single-outrigger boat designs.

== Terminology == The word "trimaran" is a portmanteau of "tri" and "(cata)maran", a term that is thought to have been coined by Victor Tchetchet, a pioneering, Ukrainian-born modern multihull designer. Trimarans consist of a main hull connected to outrigger floats on either side by a crossbeam, wing, or other form of superstructure—the traditional Polynesian terms for the hull, each float and connector are vaka, ama and aka, respectively (although trimarans are not traditionally Polynesian, since they instead use single-outrigger and catamaran configurations).