If your dad used to play in a punk band, but is now a computer programmer, you could call him an erstwhile punk rocker. Erstwhile means "former."

Erstwhile comes from Old English and is a formal way to say "former." You can go to your class reunion 20 years after you graduate high school and see your erstwhile friends. That means that they had been your friends, but you lost touch with them, so that they weren't friends of yours anymore. Erstwhile can also be used as an adverb, meaning “formerly or once” — “Erstwhile, I was a member of the high school debate team.”

Definitions of erstwhile
  1. adjective
    belonging to some prior time
    erstwhile friend”
    synonyms: former, old, one-time, onetime, quondam, sometime
    earlier than the present time; no longer current
  2. adverb
    at a previous time
    synonyms: at one time, erst, formerly, once
Word Family

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