an·​cil·​lary ˈan(t)-sə-ˌler-ē How to pronounce ancillary (audio)
 especially British  an-ˈsi-lə-rē
: subordinate, subsidiary
the main factory and its ancillary plants
: auxiliary, supplementary
the need for ancillary evidence
ancillary expenses
ancillary equipment
ancillary noun

Did you know?

If you’re already familiar with ancillary, pull up a chair and help yourself to a side dish of trivia. The word comes from the Latin word ancilla, meaning "a female servant," which also gave us the rarer English word ancilla, meaning "an aid to achieving or mastering something difficult." While the English ancilla (which made its debut a couple of centuries after ancillary) is unlikely to be encountered except in very specialized contexts (such as philosophy or quantum computing), ancillary picks up on the notion of providing aid or support in a way that supplements something else. In particular, the word often describes something that is in a position of secondary importance, such as the "ancillary products in a company's line."

Examples of ancillary in a Sentence

The lockout rocked the NHL, but among the ancillary benefits has been the emergence of young players who apprenticed for an additional season in the minors … Michael Farber, Sports Illustrated, 21 Nov. 2005
I am in love with a man who is in love with boats. As far as ancillary loves are concerned, I understand things could be worse. Sadly, I do not love boats. Ann Patchett, Gourmet, May 2003
Traditionally museums have been built to house collections, and for ancillary functions such as storage, conservation, administration, and education. Jayne Merkel, Wilson Quarterly, Winter 2002
Paleolithic hunters and gatherers obtained an abundance of complete protein, mostly from wild game; their vegetable foods were an ancillary protein source. This pattern prevailed until agriculture transformed it, shifting the human diet away from meat and toward plant food. S. Boyd Eaton et al., The Paleolithic Prescription, 1988
The company hopes to boost its sales by releasing ancillary products.
Recent Examples on the Web Surreal moments The ancillary stuff all disappears by degrees now. Greg Cote, Miami Herald, 1 July 2024 The conversation capped with a discussion about artificial intelligence, which many Hollywood guilds (and many others in ancillary businesses) fear. Matt Donnelly, Variety, 22 June 2024 All of these rights require government programs with lots of spending, and lots of taxes to pay for the spending, not to mention lots of regulations to shape the government and ancillary civil-society programs. Charles Kesler, National Review, 20 June 2024 While the filing does not identify the shareholder responsible for the board exits, Chicken Soup for the Soul Holdings, which controls the publishing rights to the namesake franchise as well as ancillary businesses like a pet food line, has accumulated a large stake in CSSE in recent months. Dade Hayes, Deadline, 17 June 2024 See all Example Sentences for ancillary 

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'ancillary.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History


see ancilla

First Known Use

1663, in the meaning defined at sense 1

Time Traveler
The first known use of ancillary was in 1663


Dictionary Entries Near ancillary

Cite this Entry

“Ancillary.” Dictionary, Merriam-Webster, Accessed 18 Jul. 2024.

Medical Definition


1 of 2 adjective
ˈan(t)-sə-ˌler-ē, especially British an-ˈsil-ə-rē
: being auxiliary or supplementary
use of a drug as ancillary to surgical treatment
ancillary staff
ancillary diagnostic services


2 of 2 noun
plural ancillaries
British : one who assists or is supplementary to another person
: a supplemental diagnostic or therapeutic medical service (as magnetic resonance imaging or radiotherapy)

Legal Definition


: having a subordinate, subsidiary, or secondary nature
ancillary functions
an ancillary agreement
: serving as a supplement or addition
ancillary documents
: directly related
ancillary claims
Last Updated: - Updated example sentences
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