If "appeal" means to attract or interest someone:
* Repel: To push away or disgust.
* Repulse: To cause aversion or disgust.
* Disgust: To cause strong feelings of revulsion or disapproval.
* Offend: To cause someone to feel hurt or upset.
* Turn off: To cause someone to lose interest.
If "appeal" means to make a formal request:
* Deny: To refuse to grant a request.
* Reject: To refuse to accept something.
* Disregard: To ignore something completely.
* Dismiss: To reject something as unimportant.
* Countermand: To cancel or revoke a previous order.
If "appeal" means the quality of being attractive or interesting:
* Unattractiveness: The state of not being appealing or attractive.
* Boredom: The state of being uninterested or unexcited.
* Dullness: The state of being uninteresting or lacking excitement.
* Repulsiveness: The quality of being disgusting or repulsive.
If "appeal" means a formal request for a decision to be reviewed:
* Affirmation: The act of confirming a previous decision.
* Upholding: To maintain a previous decision.
* Rejection: To refuse to review a decision.
To give you the most accurate antonym, please provide the sentence or context where "appeal" is being used.