renounce

Concise Oxford English Dictionary © 2008 Oxford University Press:
renounce/rɪˈnaʊns/

▶verb

• 1 formally declare one's abandonment of (a claim, right, or possession).

  ■ Law refuse or resign a right or position, especially one as an heir or trustee.

• 2 refuse to recognize any longer.

• 3 abandon (a cause, bad habit, or way of life).

– derivatives
renounceable adjective,
renouncement noun,
renouncer noun.

– origin ME: from OFr. renoncer, from L. renuntiare ‘protest against’.