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absurd; foolish; stupid; silly; nonsense; ludicrous; preposterous; laughable; ridiculous
そんな馬鹿らしい話は信じられない。
I can't believe such a ridiculous story.
そんなことで怒るのは馬鹿らしかった。
Getting angry over something like that was absurd.
彼の意見は馬鹿らしくないと思う。
I don't think his opinion is absurd.