何様(なにさま)person of importance, a somebody, absolutely, certainly, to be sure

あの偉(えら)そうな態度(たいど)…彼女(かのじょ)は何様(なにさま)なんだろう…。

That arrogant attitude... Who does she think she is... a person of importance? {person of importance, a somebody, absolutely, certainly, to be sure}

上司(じょうし)が部下(ぶか)に：「君(きみ)は傲慢(ごうまん)だ！何様(なにさま)のつもりなんだ？」

The boss says to his subordinate: "You are arrogant! Who do you think you are, a person of importance?" {person of importance, a somebody, absolutely, certainly, to be sure}

彼(かれ)は何様(なにさま)でもあるまいし、雑用(ざつよう)くらい自分(じぶん)でやるべきだ。

He's not some person of importance, he should certainly do chores by himself. {person of importance, a somebody, absolutely, certainly, to be sure}

武士(ぶし)：「貴様(きさま)、何様(なにさま)だ？そこで立(た)ち止(ど)まって正体(しょうたい)を明(あ)かすのだ！」

Samurai: "Who do you think you are? Stop right there and reveal your identity!" {person of importance, a somebody, absolutely, certainly, to be sure}

「一体(いったい)何様(なにさま)のつもり？」という同僚(どうりょう)の声(こえ)をよそに、彼(かれ)は会社(かいしゃ)で威張(いば)り続(つづ)けている。

Ignoring the voice of his colleague asking, "Who does he think he is, acting all important?", he continues to strut around the company. {person of importance, a somebody, absolutely, certainly, to be sure}