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to lose
to miss (a chance, opportunity)
to lose (a loved one); to be bereaved of
to concede (goals, points, etc.)
事故で大切な友人を喪ってしまった。
I lost a dear friend in the accident.
信頼を喪うのは一瞬だが取り戻すのは難しい。
Losing trust takes a moment, but regaining it is hard.
やる気を喪わないように目標を設定する。
I set goals so I don't lose motivation.