The term "right-hand woman" describes someone who is a trusted and reliable assistant or close confidant. Antonyms for this phrase would be "left-hand person" or "second-in-command." These terms suggest a lesser degree of trust, authority, or importance. Other antonyms could be "opponent," "adversary," or "enemy," which would imply a negative relationship rather than a partnership. "Unreliable," "distrustful," and "incompetent" are also opposite words that would suggest the opposite of a "right-hand woman." Ultimately, the antonyms for "right-hand woman" would depend on whether one is looking for the opposite in terms of trust, authority, or relational dynamics.