くたばれdrop dead!, go to hell!, fuck you!, shove it!

お前(まえ)なんか大嫌(だいきら)いだ！くたばれ！

I absolutely hate you! Drop dead! {drop dead!, go to hell!, fuck you!, shove it!}

くたばれと暴言(ぼうげん)を吐(は)いた生徒(せいと)に罰(ばつ)を与(あた)えました。

The student who spewed abuse saying "drop dead" was punished. {drop dead!, go to hell!, fuck you!, shove it!}

ライバル：「お前(まえ)はここでくたばれ！勝負(しょうぶ)に勝(か)つのはこの俺(おれ)だ！」

Rival: "Drop dead right here! I'm the one who's going to win this match!" {drop dead!, go to hell!, fuck you!, shove it!}

自分(じぶん)の姪(めい)を殺(ころ)された叔母(おば)は殺人(さつじん)犯(はん)に向(む)かって悲痛(ひつう)な声(こえ)でくたばれと叫(さけ)んだ。

The aunt, who had her niece killed, screamed "Drop dead!" at the murderer with a voice full of grief. {drop dead!, go to hell!, fuck you!, shove it!}

私(わたし)に言(い)わせると弟(おとうと)の「くたばれ」には特(とく)に何(なん)の意味(いみ)も込(こ)められていません。

In my opinion, my brother's "drop dead!" doesn't particularly carry any meaning. {drop dead!, go to hell!, fuck you!, shove it!}