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inadequacy; inappropriateness; unfitness; impropriety
不適当な服装で参加してはいけない。
You must not attend in inappropriate attire.
その発言は場の空気に不適当だった。
That remark was inappropriate for the atmosphere.
その行為は職場のルールに照らして不適当と判断された。
The conduct was judged inappropriate in light of workplace rules.