former
adjective /ˈfɔːmə(r)/
  /ˈfɔːrmər/
[only before noun]Idioms - that existed in earlier times synonym past (3)
- This fine ruin was, in former times, a royal castle.
 - This beautiful old building has been restored to its former glory.
 - her former life as a Russian ballerina
 
 - that used to have a particular position or status in the past synonym previous, one-time (1)
- the 41-year-old former world champion
 - the former president/prime minister
 - former South African president Nelson Mandela
 - both current and former employees
 - a former staff member
 - my former boss/colleague/wife
 - the countries of the former Soviet Union
 - former Portuguese colonies
 
 - the former…used to refer to the first of two things or people mentioned
- The former option would be much more sensible.
 
 
Word OriginMiddle English: from Old English forma ‘first’ + -er.
Idioms 
be a shadow/ghost of your former self 
- to not have the strength, influence, etc. that you used to have
- When his career ended, he became a shadow of his former self.