Non-acceptance refers to the act of refusing to approve or agree with something. However, there are several antonyms or opposite words that can be used in place of non-acceptance. These antonyms include acceptance, approval, agreement, endorsement, affirmation, consent, and concurrence. Acceptance refers to the act of agreeing to or approving of something, while approval reflects a positive assessment of something. Agreement refers to a state of being in harmony with something, while endorsement implies an expression of support or recommendation for something. Affirmation and consent, on the other hand, refer to giving approval or agreement based on personal beliefs or values. Finally, concurrence suggests agreement or compliance with something.