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shameful; disgraceful; unsightly; indecent; unseemly; unbecoming; improper
人前で喧嘩するなんてみっともない。
It's shameful to fight in public.
試合で負けて泣く姿はみっともなかった。
Crying after losing the match was disgraceful.
努力している姿はみっともなくないと思う。
I think the sight of someone working hard isn't shameful.