innermost feelings; heartfelt
Formal, often used in written expressions of gratitude, apology, or condolence. Common in phrases like 衷心より (heartfelt) or 衷心から (from the bottom of one's heart).
Please accept my heartfelt condolences.
I express my heartfelt gratitude for your support.
I offer my heartfelt condolences.
I sincerely apologize from the bottom of my heart.
本心 refers to one's true feelings or real intention, often contrasted with outward behavior, whereas 衷心 emphasizes deep, sincere emotion itself.
真心 is a warmer, more general word for sincere feeling used in everyday contexts (真心を込めて), while 衷心 is stiffly formal and confined to set expressions of gratitude, apology, or condolence.
中心 (ちゅうしん) means 'center/middle' and is a completely different word that just happens to share the same reading as 衷心 (ちゅうしん), which means 'heartfelt feelings'.
Compound of 衷 (inner feelings, heart) and 心 (heart, mind). The kanji 衷 carries a sense of innermost or sincere, reinforcing the meaning of deep, genuine emotion.