auxiliary Definition

offering or providing help

functioning in a subsidiary capacity

accompanying another verb and typically expressing person, number, mood, or tense

an auxiliary person, group, or device; specifically : a member of a foreign force serving a nation at war

a Roman Catholic titular bishop assisting a diocesan bishop and not having the right of succession —called also auxiliary bishop

a sailing boat or ship equipped with a supplementary inboard engine

a verb (such as have, be, may, do, shall, will, can, or must) that is used with another verb to show the verb's tense, to form a question, etc.

an auxiliary verb (such as can, must, might, may) that is characteristically used with a verb of predication and expresses a modal modification and that in English differs formally from other verbs in lacking -s and -ing forms

an auxiliary verb

a verb (such as can, could, shall, should, ought to, will, or would) that is usually used with another verb to express ideas such as possibility, necessity, and permission