Meaning of apostolic succession

apostol'ic succes'sion

Pronunciation: [key]
— Rom. Cath. Ch., Orth. Ch., Anglican Ch. Rom. Cath. Ch.,Orth. Ch.,Anglican Ch.
  1. the unbroken line of succession beginning with the apostles and perpetuated through bishops, considered essential for orders and sacraments to be valid.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.