Definition of "confirmation"

confirmation

/ˌkɑn.fəɹˈmeɪ.ʃən/

noun
countable and uncountable, plural confirmations
1. An official indicator that things will happen as planned.
2. A verification that something is true or has happened.
  Quotations
  They declare ringing confirmation for their theories even in the face of feeble data.
  1999 March 20, Natalie Angiers, The Guardian
  The thing is, we've even had formal confirmation from Government itself that the crucial research required to make such sweeping claims hasn't been done!
  2022 January 12, Nigel Harris, “Comment: Unhappy start to 2022”, in RAIL, number 948, page 3
3. A ceremony of sealing and conscious acknowledgement of the faith in many Christian churches, typically around the ages of 14 to 18; considered a sacrament in some churches, including Catholicism, but not in most Protestant churches.
  Quotations
  You got a nice white dress / and a party on your confirmation. / You've got a brand new soul, / mm, and a cross of gold.
  1977, “Only the Good Die Young”, in Billy Joel (music), The Stranger
4. (law) An act whereby something conditional or voidable is made sure and unavoidable, especially the possession of an estate.