一いっ徹てつ者もの

noun

stubborn person; diehard

Describes a person who is obstinate and refuses to change their mind or ways. Often carries a negative connotation of inflexibility.

• 彼かれは一いっ徹てつ者もので、一いち度ど決きめたら絶ぜっ対たいに曲まげない。

  He is a stubborn person; once he decides something, he never backs down.

• あの一いっ徹てつ者ものを説せっ得とくするのは無む理りだ。

  It's impossible to persuade that diehard.