olemus
sõltub kontekstist

Wiktionary:
1. the action of reverting something
Synonym: reversal
2. the action of returning to a former condition or practice
Synonym: regression
3. the fact of being turned the reverse way
4. the action of turning something the reverse way
5.(property law) he return of an estate to the donor or grantor after expiry of the grant
9. (genetics) the return of a genetic characteristic after a period of suppression
Synonym: backmutation

näiteid
https://en.wikipedia.org/wiki/Reversion_(software_development)