Dictionary / Vocabulary / 頑固一徹
がんこいってつ
stubborn; obstinate; adamant; immovable
頑固一徹のボスだと思っていたけれど、結構かわいいところもあるじゃない。
I thought our boss was stubborn as a mule but actually he has his cute side.
父ちゃんは仕事に頑固一徹な人間です。
My dad is a stubborn man at his job.