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constraint; reserve; feeling hesitant; being afraid of troubling someone
遠慮なく使ってほしいと言われて気兼ねなく借りた。
They said to use it freely, so I borrowed it without reserve.
一人暮らしは気兼ねなく過ごせるのが良い。
Living alone is nice because you can live without worrying about others.
気兼ねして本音を言えないことがある。
Sometimes I can't speak my mind due to feeling constrained.