Emily Dickinson Lexicon

AUX-IL'IA-RY, n.

1. A helper; an assistant; a confederate in some action, enterprise or undertaking.
2. In grammar, a verb which helps to form the modes and tenses of other verbs; as, have, be, may, can, do, must, shall, and will, in English; être and avoir, in French; avére and essere in Italian; estar and haber, in Spanish.