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shameful; disgraceful; unsightly; indecent; unseemly; unbecoming; improper
そんな見っともない格好で外に出ないで欲しいな。
I wish you wouldn't go out in such an unsightly appearance.
酔って大声を出した彼の姿は見っともなかった。
His appearance, shouting loudly while drunk, was disgraceful.
きちんと服を着ていれば見っともなくないよ。
If you dress properly, it won't look unseemly.