From Longman Dictionary of Contemporary Englishbe waiting in the wingsbe waiting in the wingsWAITto be ready to do something if it is necessary or if a suitable time comes Other firms are waiting in the wings, ready to step in and make an offer should the current deal fall through. → wait
Examples from the Corpus
be waiting in the wings• A new comedy wave, I suppose, is waiting in the wings.• If so, the Democrats would be waiting in the wings.• Shortstop Jose Vizcaino is a free agent, and if his price is too high Rich Aurilia is waiting in the wings.• The world's list of mammals is about five thousand long, but three thousand more may be waiting in the wings.• Young, a talented quarterback, was waiting in the wings for the day when Montana couldn't play. 