Betray is defined as the act of breaking faith or trust with someone. Some antonyms for betray include support, defend, aid, assist, and protect. These words imply loyalty, honesty, and commitment towards others. Supporting someone means standing by them even through difficult times, while defending someone means protecting them from harm or danger. Aiding and assisting someone means providing necessary help or resources, while protecting someone involves shielding them from potential harm. Engaging in acts that exhibit these qualities demonstrate one's trustworthiness and reliability. In summary, the opposite of betraying someone is standing by their side, being their confidant and protector.