Definition 1: formally declare one's abandonment of (a claim, right, or possession).
Sentence 1: "Isabella offered to renounce her son's claim to the French Crown"
Definition 2: reject and stop using or consuming.
Sentence 2: "he renounced drugs and alcohol completely"
Definition 3: refuse or resign a right or position, especially one as an heir or trustee.
Sentence 3: "there will be forms enabling the allottee to renounce"
Hope this helps :)