[awg-zil-yuh-ree, -zil-uh-]
  1. additional; supplementary; reserve: an auxiliary police force.
  2. used as a substitute or reserve in case of need: The hospital has an auxiliary power system in case of a blackout.
  3. (of a boat) having an engine that can be used to supplement the sails: an auxiliary yawl.
  4. giving support; serving as an aid; helpful: The mind and emotions are auxiliary to each other. Passion is auxiliary to art.
noun, plural aux·il·ia·ries.
  1. a person or thing that gives aid of any kind; helper.
  2. an organization allied with, but subsidiary to, a main body of restricted membership, especially one composed of members' relatives: The men's club and the ladies' auxiliary were merged into one organization.
  3. auxiliary verb.
  4. auxiliaries, foreign troops in the service of a nation at war.
  5. Navy. a naval vessel designed for other than combat purposes, as a tug, supply ship, or transport.
  6. Nautical. a sailing vessel carrying an auxiliary propulsion engine or engines.

Origin of auxiliary

1595–1605; < Latin auxiliārius assisting, aiding, helping, equivalent to auxili(um) aid, help (aux(us) increased, augmented (past participle of augēre: aug- increase + -sus, variant of -tus past participle suffix) + -ilium noun suffix) + -ārius -ary

Synonyms for auxiliary Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018

Examples from the Web for auxiliaries

Contemporary Examples of auxiliaries

  • Their auxiliaries, until the advent of the French, were wholly undisciplined.

    The Daily Beast logo
    Washington in Victory

    Piers Brendon

    October 10, 2008

Historical Examples of auxiliaries

British Dictionary definitions for auxiliaries


pl n
  1. foreign or allied troops serving another nation; mercenaries


  1. secondary or supplementary
  2. supporting
  3. nautical (of a sailing vessel) having an enginean auxiliary sloop
noun plural -ries
  1. a person or thing that supports or supplements; subordinate or assistant
  2. nautical
    1. a sailing vessel with an engine
    2. the engine of such a vessel
  3. navy a vessel such as a tug, hospital ship, etc, not used for combat

Word Origin for auxiliary

C17: from Latin auxiliārius bringing aid, from auxilium help, from augēre to increase, enlarge, strengthen
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Word Origin and History for auxiliaries



c.1600, from Latin auxiliaris "helpful," from auxilium "aid, help, support," related to auctus, past participle of augere "to increase" (see augment).



"foreign troops in service of a nation at war," c.1600, from auxiliary (adj.). Related: Auxiliaries.

Online Etymology Dictionary, © 2010 Douglas Harper

auxiliaries in Medicine


[ôg-zĭlyə-rē, -zĭlə-rē]
  1. Functioning in an augmenting capacity; supplementary.
  2. Functioning as a subordinate; secondary.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.