I-adjective (keiyoushi)
tenacious; tough; enduring; dogged; headstrong; stubborn; obstinate; unyielding
彼は結構しぶといね。転んでもただでは起きぬ、いい根性しているよ。He's a tenacious guy who always manages to come out on top. He's the kind of guy who can turn any situation to his advantage.