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to scorn; to despise; to hold in contempt; to look down on; to disdain
相手を蔑んではいけない。
You shouldn't look down on others.
彼は仕事のできない人を蔑んだ。
He looked down on people who weren't good at their jobs.
人を蔑む態度は周りを不快にさせる。
An attitude of contempt for others makes those around you uncomfortable.