auxiliary

adjective
aux·​il·​ia·​ry | \ȯg-ˈzil-yə-rē, -ˈzil-rē, -ˈzi-lə- \

Definition of auxiliary 

(Entry 1 of 2)

1a : offering or providing help

b : functioning in a subsidiary capacity an auxiliary branch of the state university

2 of a verb : accompanying another verb and typically expressing person, number, mood, or tense In "I will go," the word "will" is an auxiliary verb.

3a : supplementary a telescope with its auxiliary apparatus

b : constituting a reserve an auxiliary power plant an auxiliary police force

4 of a boat : equipped with sails and a supplementary inboard engine an auxiliary sloop

auxiliary

noun
aux·​il·​ia·​ry | \ȯg-ˈzil-yə-rē, -ˈzil-rē, -ˈzi-lə-\
plural auxiliaries

Definition of auxiliary (Entry 2 of 2)

1a : an auxiliary person, group, or device specifically : a member of a foreign force serving a nation at war

b : a Roman Catholic titular bishop assisting a diocesan bishop and not having the right of succession

called also auxiliary bishop

2 : a sailing boat or ship equipped with a supplementary inboard engine

3 grammar : an auxiliary verb

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Synonyms & Antonyms for auxiliary

Synonyms: Adjective

accessorial, accessory, appurtenant, peripheral, supplemental, supplementary

Antonyms: Adjective

chief, main, principal

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Did You Know?

Adjective

Auxiliary can be used in a wide range of capacities in English to describe a person or thing that assists another. A fire department may bring in auxiliary units, for example, to battle a tough blaze, or a sailboat may be equipped with auxiliary engines to supply propulsion when the wind disappears. In grammar, an auxiliary verb assists another (main) verb to express person, number, mood, or tense, as have in "They have been informed." The Latin source of auxiliary is auxilium, meaning "help."

Examples of auxiliary in a Sentence

Adjective

Travelers have also been griping about a lack of air-conditioning while planes are on the tarmac—even after delays stretch for hours. Airlines blame the problem on a breakdown of a plane's auxiliary power unit. — Darren Everson, Wall Street Journal, 8 Aug. 2007 However, on March 1, 1896, Italian forces underwent a stunning defeat at Adwa, where they fought against the warriors of the Abyssinian emperor, Menelik. Some five thousand Italian troops and two thousand native auxiliary troops had been killed or captured, and the colony had been lost. — Mirella Tenderini et al., The Duke of the Abruzzi, 1997 The rotund 6'1", 235-pound object of their affections hasn't played a day of major league baseball, he dresses in the auxiliary locker room, and he isn't even listed on Boston's 40-man roster. But after a resplendent summer last year at Triple A Pawtucket and a winter of panegyrics from a giddy Boston press, first baseman Maurice Samuel (Mo) Vaughn, 23, has arrived as a "real" rookie who everyone in Red Sox-land hopes is the real thing. — Nicholas Dawidoff, Sports Illustrated, 1 Apr. 1991 a sailboat with an auxiliary engine the auditorium has an auxiliary cooling system used only on particularly sweltering days

Noun

In 1944 Forrestal also began a program of sending black enlisted men to serve in a limited number of fleet auxiliaries. These were still not warships, but they were seagoing vessels and closer to the fighting Navy than the small harbor-defense craft and harbor auxiliaries that had initially been open to black crews. The Golden Thirteen, 1993 Roman cavalry was poorly developed; they relied on wings, called alae, of horsemen supplied by their auxiliaries. The favorite Roman battle formation was of a triple line of cohorts with alae sweeping the flanks. — Kenneth P. Czech, MHQ : The Quarterly Journal of Military History, Autumn 1992

Recent Examples on the Web: Adjective

Archbishop Byrnes, formerly Detroit’s former auxiliary bishop, formally took the reins as Archbishop Apuron’s successor earlier this year. Tom Corrigan, WSJ, "Guam’s Archdiocese of Agana to File for Bankruptcy," 7 Nov. 2018 Another large storage box behind the front two seats houses a deep cycle auxiliary battery that powers the dimmable LED lighting, two USB power ports, and the 31-quart fridge. Megan Barber, Curbed, "Modular camper van sleeps two and hauls gear, asks $37K," 22 Oct. 2018 Designed to accommodate future weapons such as railguns and lasers, the Zumwalts integrate feature an integrated power system consisting of two main turbine generators, two auxiliary turbine generators, and two 34.6MW advanced induction motors. Kyle Mizokami, Popular Mechanics, "Navy Stealth Destroyer Gets a 15-Ton Engine Transplant," 5 Sep. 2018 The raid was a success, but due to the extreme distance the bombers had to be fitted with an auxiliary fuel tank and lightened significantly, even leaving behind most of their machine guns. Matthew Moss, Popular Mechanics, "How the American Aircraft Carrier Became King of the Seas," 22 May 2018 The express lane extension and the auxiliary lane between Little Gunpowder Falls and Route 152 will be built between July 2020 and December 2022, according to the MDTA schedule. Allan Vought, The Aegis, "Area residents get a long, detailed look at I-95 toll lane extension during Joppa presentation," 27 Feb. 2018 The Pentagon said Keown was flying one of four aircraft of the 36th Fighter Squadron, 8th Fighter Group on a mission to locate a missing B-25 bomber when the weather turned bad and the fighters headed to an auxiliary airfield on April 16, 1944. CBS News, "Pilot missing since World War II buried at Arlington National Cemetery," 15 June 2018 Robertson, who also worked as an auxiliary member of the Olmsted Falls Police Department and U.S. Coast Guard and was a volunteer firefighter in Columbia Station and Lodi, was stripped of his duty when detectives obtained an arrest warrant in March. Cory Shaffer, cleveland.com, "Former Olmsted Falls Boy Scout leader pleads guilty to sex charges on first day of trial," 2 May 2018 It is requested that all post and auxiliary members be present. Courant Community, "Community News For The Windsor Locks Edition," 12 June 2018

Recent Examples on the Web: Noun

For more information about the fundraiser, visit the GoFundMe page, or the auxiliary's website. Samantha West, Milwaukee Journal Sentinel, "Lots of Milwaukee firehouses lack laundry machines. Here's why that's a problem.," 3 July 2018 Some groups are official police auxiliaries but others are essentially costumed social clubs. Washington Post, "Cossacks under scrutiny as they prepare to guard World Cup," 8 June 2018 Proceeds from the event will go to the auxiliary's Firefighter Cancer Prevention Initiative. Ashley Luthern, Milwaukee Journal Sentinel, "Chili cook-off benefits Milwaukee firefighter cancer prevention initiative," 23 Mar. 2018 Proceeds from the event will go to the auxiliary's Firefighter Cancer Prevention Initiative. Ashley Luthern, Milwaukee Journal Sentinel, "Chili cook-off benefits Milwaukee firefighter cancer prevention initiative," 23 Mar. 2018 Proceeds from the event will go to the auxiliary's Firefighter Cancer Prevention Initiative. Ashley Luthern, Milwaukee Journal Sentinel, "Chili cook-off benefits Milwaukee firefighter cancer prevention initiative," 23 Mar. 2018 These forces function as auxiliaries to Syrian military power, having participated in both battles and sieges on behalf of Assad and Iran. Behnam Ben Taleblu, Fortune, "Commentary: How Trump Can Neutralize Assad in Syria," 13 Apr. 2018 On March 27, some 80 members, auxiliaries and guests gathered at the league's clubhouse to sip and sup as the 75th anniversary of the organization's founding in Glendale was celebrated. Ruth Sowby Rands, latimes.com, "On the Town: Spring is sprung with Garden Party Tea," 9 Apr. 2018 The grand fleet of the Navy with all its auxiliaries was informed of the existence of a state of war and its full 400 ships and 100,000 men were ordered to mobilize at once for war service. Express-news Archives, San Antonio Express-News, "President Wilson launched U.S. into Great War in April 1917," 5 Apr. 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'auxiliary.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of auxiliary

Adjective

15th century, in the meaning defined at sense 1a

Noun

1567, in the meaning defined at sense 1a

History and Etymology for auxiliary

Adjective

Latin auxiliaris, from auxilium help; akin to Latin augēre to increase — more at eke

Noun

see auxiliary entry 1

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Statistics for auxiliary

Last Updated

16 Nov 2018

Look-up Popularity

Time Traveler for auxiliary

The first known use of auxiliary was in the 15th century

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More Definitions for auxiliary

auxiliary

adjective

English Language Learners Definition of auxiliary

 (Entry 1 of 2)

: available to provide extra help, power, etc., when it is needed

auxiliary

noun

English Language Learners Definition of auxiliary (Entry 2 of 2)

: a group that provides help or assistance

auxiliary

adjective
aux·​il·​ia·​ry | \ȯg-ˈzi-lyə-rē, -ˈzi-lə-rē, -ˈzil-rē\

Kids Definition of auxiliary

 (Entry 1 of 2)

: available to provide something extra an auxiliary engine

auxiliary

noun
plural auxiliaries

Kids Definition of auxiliary (Entry 2 of 2)

1 : a group that provides assistance

auxiliary

adjective
aux·​il·​ia·​ry | \ȯg-ˈzil-yə-rē, -ˈzil-(ə-)rē \

Medical Definition of auxiliary 

(Entry 1 of 2)

: serving to supplement or assist auxiliary springs in a dental appliance

auxiliary

noun

Medical Definition of auxiliary (Entry 2 of 2)

1 : one who assists or serves another person especially in dentistry

2 : an organization that assists (as by donations or volunteer services) the work especially of a hospital

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