Definition of: auxiliary

(ôg·zil′yər·ē, -zil′ər-) adjective
1. Giving or furnishing aid.
2. Subsidiary; accessory.
—noun plural ·ries
1. One who or that which aids or helps; assistant; associate.
2. Gram. a A verb that helps to express the tense, mood, voice, or aspect of another verb, as have in “We have gone,” may in “I may leave tomorrow”: also called helping verb. Also auxiliary verb. b A word which functions as a subordinate element in a sentence and is fully meaningful only in association with the main words, as a preposition or conjunction.
3. plural Foreign troops associated with those of a nation at war.
4. An auxiliary vessel. [ <L auxiliarius <auxilium a help < augere increase] Synonyms (noun): accessory, aid, ally, assistant, coadjutor, confederate, helper, mercenary, promoter, subordinate. Allies unite as equals; auxiliaries, in military usage, are troops of one nation uniting with the armies, and acting under the orders, of another. Mercenaries serve only for pay; auxiliaries often for reasons of state, policy, or patriotism as well. Compare ACCESSORY, APPENDAGE. Antonyms: antagonist, hinderer, opponent.