noun - The butterfly (colloquially among swimmers known as fly or mariposa in Spanish) is a competitive swimming stroke swum on the stomach with both arms moving simultaneously, accompanied by the butterfly kick (also known as the dolphin kick). While other styles like the breaststroke, front crawl (or freestyle), and backstroke can be swum adequately by beginners, the butterfly is a more difficult stroke that requires good technique as well as strength and coordination. Many swimmers and coaches consider it the most difficult swimming style. It is the newest swimming style swum in competition, first swum in 1933 and originating out of breaststroke. The main difficulty for beginners is the synchronous over-water recovery, especially when combined with breathing, since both arms, the head, shoulders and part of the chest have to be lifted out of the water for these tasks.