A humble polite expression used to reply to a compliment or special treatment, meaning "you flatter me" or "I don't deserve such honor".

To feel unable or unwilling to take on a responsibility, honor, or position

(Literary) (of words or actions) inappropriate, improper, or unbecoming

To be unwilling or afraid to take responsibility for one's own actions (often in the phrase 敢做不敢当 gǎn​zuò​bù​gǎn​dāng)