康熙字典
【卯集上】【心字部】㤁 ·康熙筆画:8 ·部外筆画:4
《說文》忝本字。《長箋》从天心會意。以天求心,每自慚愧寓戒也。
(standard form of 忝) to disgrace; to insult, to condescend