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guilty (feeling, conscience, look, etc.); (feeling) uneasy
友達に嘘をつき、後ろめたい。
I felt guilty for lying to my friend.
彼女からの親切が、少し後ろめたかった。
Her kindness made me feel a little uneasy, as if I didn't deserve it.
家族に半分の真実を伝えて、後ろめたくてたまらなかった。
I couldn't help but feel terribly guilty after telling my family only half the truth.