Extreme
noun, な adjective
At the extreme edge, which is just the extreme.
極端 means something is taken to the extreme without moderation, so it generally has a negative connotation.
This is a jukugo word, which usually means on'yomi readings from the kanji. If you know the readings of your kanji you'll know how to read this as well.
ちょっと嫌なことがあったからって会社を辞めるなんて、武井さんも極端ですねぇ！
Mr. Takei, you're being quite extreme by quitting the company just because something unpleasant happened, don't you think?
年金ってさ、めっちゃ極端に言えば「生き残れたラッキーな人に対して、若い人にお金を出させる」仕組みでしょ？
When you put it in extreme terms, isn't pension basically a system where 'the lucky survivors' make the young people pay for it?
私は制服って素晴らしいと思ってるんです。極端な話、皆が同じ服を着ることで、それぞれの中身の個性が際立つと思うんですよ。
I think uniforms are fantastic to be honest. In extreme terms, I believe that everyone wearing the same clothing makes their individual personalities stand out.
君は奇跡を起こすことができるかもしれない。でも、僕は君には極端なことは避けてもらいたいんだよ。
You may be able to perform miracles, but I want you to avoid doing extreme things.