The antonyms for "under wing" would be "separate," "independent," "alone," "isolated," or "detached." "Under wing" implies being protected or supported by someone or something, often a mentor or caregiver. In contrast, the opposite would indicate a lack of support, guidance, or protection. It may connote a sense of vulnerability or uncertainty. When one is "under wing," they experience a sense of comfort and security, while the antonyms imply a lack of these qualities. The opposite of "under wing" can be used to suggest self-sufficiency, autonomy, or the ability to prosper without external assistance.