loyalty; faithfulness
彼の忠誠心は揺るぎなかった。
His loyalty was unwavering.
忠誠心は試練の中でこそ試される。
Loyalty is tested in times of hardship.
部下の忠誠心を信じて大きな権限を委ねた。
Trusting his subordinates' loyalty, he delegated significant authority.