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reserve; modesty; hesitation; restraint
忌憚のないご意見をお聞かせください。
Please let us hear your candid opinions.
忌憚なく発言できる環境が大切だ。
An environment where one can speak freely is important.
彼は忌憚なく上司に意見を述べた。
He stated his opinion to his boss without reservation.