Gung ho is an English term, with the current meaning of "overly enthusiastic or energetic".
It is thought to have originated from a catachresis of a Chinese acronym for Chinese Industrial Cooperatives, with the meaning of 'working together'.
The term was picked up by United States Marine Corps Major Evans Carlson from his New Zealand friend, Rewi Alley, one of the founders of the Chinese Industrial Cooperatives. Carlson explained in a 1943 interview: "I was trying to build up the same sort of working spirit I had seen in China where all the soldiers dedicated themselves to one idea and worked together to put that idea over. I told the boys about it again and again. I told them of the motto of the Chinese Cooperatives, Gung Ho. It means Work Together — Work in Harmony."
Later, Carlson used gung ho as a motto during his (unconventional) command of the enthusiastic 2nd Marine Raider Battalion, leading to other marines adopting the term to mean overly enthusiastic. From there, it spread throughout the U.S. Marine Corps hence the association between the two, where it was used as an expression of spirit and into American society as a whole when the phrase became the title of a 1943 war film.
