line of succession

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• noun An ordered sequence of named people who would succeed to a particular office upon the death, resignation or removal of the current occupant; constructed using the rules of an established order of succession.

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

• noun the order in which individuals are expected to succeed one another in some official position