Origin: Latin suffix -ary
Auxiliary has 5 different meanings across 2 categories:
A person or group that acts in an auxiliary manner.
"The volunteer served as an auxiliary to support the main fire brigade during the emergency."
In plain English: An auxiliary is someone who helps out with extra tasks instead of doing the main job themselves.
"The auxiliary police helped maintain order during the festival."
functioning in a supporting capacity
"the main library and its auxiliary branches"
Helping; giving assistance or support.
"The auxiliary police officer helped direct traffic during the parade."
In plain English: Auxiliary means something that helps out but isn't the main focus.
"The auxiliary engines kicked in to power the ship when the main engine failed."
Usage: Use the adjective form to describe something secondary, temporary, or provided as extra help rather than a primary function. This term is often applied to units like police forces or power systems designed specifically for backup purposes during emergencies.
The word auxiliary comes from the Latin auxiliārius, which originally meant "assistant" or "ally." It traveled into English through French to describe someone who provides help.