1. （通常指医务或军队中的）辅助人员
    An auxiliary is a person who is employed to assist other people in their work. Auxiliaries are often medical workers or members of the armed forces.

    e.g. Nursing auxiliaries provide basic care, but are not qualified nurses.
           助理护士只提供基本护理，不具备护士资格。

2. （员工、军队）辅助的，协助的
    Auxiliary staff and troops assist other staff and troops.

    e.g. The government's first concern was to augment the army and auxiliary forces.
           政府关心的首要问题是扩充军队及辅助队伍。

3. 备用的；后备的
    Auxiliary equipment is extra equipment that is available for use when necessary.

    e.g. ...an auxiliary motor.
           备用发动机
    e.g. ...auxiliary fuel tanks.
           备用油箱

4. 附属机构
    An auxiliary is an organization that is connected with, but less important than, another organization; for example, an organization for the wives of the members of the main organization.

    e.g. The restaurant is operated by the Palo Alto Auxiliary for the benefit of the Lucile Salter Packard Children's Hospital.
           这家餐厅由帕洛阿尔托附院经营，收益用来资助露西尔·帕卡德儿童医院。

5. （语法中的）助动词
    In grammar, an auxiliary or auxiliary verb is a verb which is used with a main verb, for example to form different tenses or to make the verb passive. In English, the basic auxiliary verbs are 'be', 'have', and 'do'. Modal verbs such as 'can' and 'will' are also sometimes called auxiliaries.