adjective an·cil·lary \ ˈan(t)-sə-ˌler-ē , -ˌle-rē , especially British an-ˈsi-lə-rē \
|Updated on: 10 Jul 2018

Definition of ancillary

1 : subordinate, subsidiary
  • the main factory and its ancillary plants
2 : auxiliary, supplementary
  • the need for ancillary evidence
  • ancillary expenses
  • ancillary equipment



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Examples of ancillary in a Sentence

  1. 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 FarberSports Illustrated21 Nov. 2005
  2. 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 PatchettGourmetMay 2003
  3. Traditionally museums have been built to house collections, and for ancillary functions such as storage, conservation, administration, and education. —Jayne MerkelWilson QuarterlyWinter 2002
  4. 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 Prescription1988
  5. The company hopes to boost its sales by releasing ancillary products.

Recent Examples of ancillary from the Web

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

Did You Know?

Ancillary derives from the English word ancilla, a somewhat rare word that means "an aid to achieving or mastering something difficult." That word derives from Latin, where it meant "female servant." While English "ancilla" 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."

Origin and Etymology of ancillary

ANCILLARY Defined for English Language Learners


Definition of ancillary for English Language Learners

  • : providing something additional to a main part or function

Medical Dictionary



adjective an·cil·lary \ ˈan(t)-sə-ˌler-ē, esp British an-ˈsil-ə-rē \

medical Definition of ancillary

: being auxiliary or supplementary
  • use of a drug as ancillary to surgical treatment
  • ancillary staff
  • ancillary diagnostic services




medical Definition of ancillary

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

Law Dictionary


adjective an·cil·lary \ ˈan-sə-ˌler-ē, an-ˈsi-lə-rē \

legal Definition of ancillary

1 : having a subordinate, subsidiary, or secondary nature
  • ancillary functions
  • an ancillary agreement
2 : serving as a supplement or addition
  • ancillary documents
3 : directly related
  • ancillary claims

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one who attends or assists a leader

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