Reversion
Part of speech: noun
Definition: The action of reverting something. The action of returning to a former condition or practice; reversal. The fact of being turned the reverse way. The action of turning something the reverse way. The return of an estate to the donor or grantor after expiry of the grant. An estate which has been returned in this manner. The right of succeeding to an estate, or to another possession. The right of succeeding to an office after the death or retirement of the holder. The return of a genetic characteristic after a period of suppression. A sum payable on a person's death.
Relapse
Part of speech: verb
Definition: To fall back again.To recur; to worsen, be aggravated.
Part of speech: noun
Definition: The act or situation of relapsing.
Example sentence: Why did I write 'The Emperor of All Maladies?' A 56-year-old woman with an abdominal sarcoma, having undergone two remissions and a relapse, asked me to describe what she was battling. By the time I had finished answering her, I realised that I had written 600 pages.