too eager to do something, often without thinking about the risks involved in a situation Our new salesman is rather gung-ho.I'm not sure I approve of my bank's gung-ho approach to lending. (American informal)
gung ho
Also, gung-ho. Extremely enthusiastic or dedicated, as in She was gung ho about her new job. This expression was introduced in 1942 as a training slogan for a U.S. Marine battalion, derived from what an American officer thought were Mandarin Chinese words for "work together." It was actually an abbreviation for the name of Chinese industrial cooperatives.