repudiate
Meaning: to reject, refuse to accept
Usage: Kwame made a strong case for an extension of his curfew, but his mother repudiated it with a few biting words.
renunciation
Meaning: the act of rejecting or giving up
Usage: Fiona’s renunciation of red meat resulted in weight loss, but confused those people who thought she’d been a vegetarian for years.
forsake
Meaning: to give up, renounce
Usage: He decided to forsake video games until his exams were over.