Definition of auxiliary

The word "auxiliary" is derived from the Latin word auxiliarius, which means "helping" or "providing assistance." InOld French, the word became auxilier, meaning "assistant" or "adjutant," and it was also used to refer to military auxiliary forces. In the 16th century, the word was adopted into English and initially used in a military context. Its usage expanded to describe any secondary resource, such as an auxiliary battery of artillery in support of the main force, or an auxiliary vessel accompanying a larger ship or naval fleet. By the late 19th century, the word had gained wider usage and was used to describe other types of supplementary resources as well, such as auxiliary hospitals established during times of national emergency, or auxiliary police officers to help maintain order in times of civil unrest. Today, the word "auxiliary" continues to be used in a variety of contexts to describe resources or components that provide added support, assistance, or backup to primary systems or operations.