From Longman Dictionary of Contemporary Englishpecking orderˈpecking ˌorder noun [singular] SSa social system within a group of people or animals in which each member knows who has a higher or lower rank than themselves Nobody wants to be at the bottom of the pecking order.
Examples from the Corpus
pecking order• Males compete with one another for places in a pecking order.• Beneath that principled veneer students were hammering out the usual adolescent pecking order.• He seems to have dropped down the Hollywood pecking order.• Even many six-year-olds already know that there is a reader pecking order in their classrooms.• Occasionally a foal thinks we are pretty low in the pecking order and decides to kick us.• But normally the pecking order works out by itself.• Patients are at the bottom of the pecking order and have very little say in the running of services.• Horses with the highest self-esteem are likely to be found at the top of their pecking order.From Longman Business Dictionarypecking orderˈpecking ˌorder [countable usually singular] the way that people or companies are ranked according to how important, successful etc they areThe IMF ranking is used to measure the pecking order of the world’s leading economic powers.Bonuses make it hard to tell exactly where directors stand in the corporate pecking order. → order 