Most chastened refers to a state of humility or repentance after experiencing a difficult or humiliating situation. The antonyms for this phrase could be cocky, confident, arrogant, proud, or haughty. These terms signify a lack of humility or remorse and imply a sense of superiority or entitlement. Individuals who are the opposite of most chastened may feel invincible and overconfident, believing that they are above consequences or criticism. However, it is important to remember that true strength and growth come from learning from failures and embracing humility. Being most chastened implies a willingness to grow and improve, which is a valuable trait in personal and professional development.