noun
true feelings; real intention; one's heart
Refers to what someone genuinely thinks or feels, often contrasted with outward words or behavior. Common in expressions like 本心を言う, 本心を見せる, or 本心かどうか.
彼の言葉が本心かどうかわからない。
I don't know if his words reflect his true feelings.
なかなか本心を見
He's someone who rarely shows his real intentions.
noun
right mind; senses; conscience
Used in set phrases like 本心に返る (come to one's senses) or 本心を失う (lose one's right mind). This usage is somewhat literary or formal.
彼はようやく本心に返った。
He finally came to his senses.
怒りで本心を失ってはいけない。
You must not lose your right mind in anger.