supplement

1 of 3

noun (1)

sup·​ple·​ment ˈsə-plə-mənt How to pronounce supplement (audio)
Synonyms of supplement
1
a
: something that completes or makes an addition
b
: dietary supplement
2
: a part added to or issued as a continuation of a book or periodical to correct errors or make additions
3
: an angle or arc that when added to a given angle or arc equals 180°

supplement

2 of 3

verb

sup·​ple·​ment ˈsə-plə-ˌment How to pronounce supplement (audio)
supplemented; supplementing; supplements

transitive verb

: to add or serve as a supplement to
does odd jobs to supplement his income
supplementation
ˌsə-plə-ˌmen-ˈtā-shən How to pronounce supplement (audio)
-mən-
noun
supplementer
ˈsə-plə-ˌmen-tər How to pronounce supplement (audio)
noun

supplementer

3 of 3

noun (2)

sup·​ple·​ment·​er ˈsəpləˌmentə(r) How to pronounce supplementer (audio)
plural -s
: one that supplements

Synonyms of supplement

Relevance

Noun (1)

See All Synonyms & Antonyms in Thesaurus

Examples of supplement in a Sentence

Noun (1) the supplement to the encyclopedia First-class accommodation is available for a supplement. Verb She began supplementing her diet with vitamins.
Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Noun
Monitor rainfall and supplement as needed to make sure your tree gets enough moisture. — Karen Brewer Grossman, Southern Living, 6 July 2026 Some supplements and chews are offered in different flavors to better entice your dog. — Bestreviews, Mercury News, 2 July 2026
Verb
The union supplements the regulations with a few measures of its own. — Andrea Sachs The Washington Post, Arkansas Online, 28 June 2026 The program distributes money to children and families in poverty to supplement food costs during the summer. — Kate Gray, CBS News, 29 June 2026 See All Example Sentences for supplement

Word History

Etymology

Noun (1)

Middle English, borrowed from Anglo-French & Latin; Anglo-French, borrowed from Latin supplēmentum "something added to supply a deficiency or make up a whole, reinforcement," from supplēre "to fill up, complete, raise to its full complement" + -mentum -ment — more at supply entry 2

Verb and Noun (2)

derivative of supplement entry 1

First Known Use

Noun (1)

14th century, in the meaning defined at sense 1a

Verb

1659, in the meaning defined above

Time Traveler
The first known use of supplement was in the 14th century

Phrases Containing supplement

Browse Nearby Words

supplely
supplement
supplemental
See all Nearby Words

Cite this Entry

“Supplement.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/supplement. Accessed 7 Jul. 2026.

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Kids Definition

supplement

1 of 2 noun
sup·​ple·​ment ˈsəp-lə-mənt How to pronounce supplement (audio)
1
: something that supplies what is needed or makes an addition
vitamin pills used as dietary supplements
2
: an arc or angle that when added to a given arc or angle equals 180 degrees
supplemental
ˌsəp-lə-ˈment-ᵊl
adjective

supplement

2 of 2 verb
sup·​ple·​ment ˈsəp-lə-ˌment How to pronounce supplement (audio)
: to add to
supplement their incomes by doing odd jobs
supplementation
ˌsəp-lə-ˌmen-ˈtā-shən How to pronounce supplement (audio)
-mən-
noun

Medical Definition

supplement

1 of 2 noun
sup·​ple·​ment ˈsəp-lə-mənt How to pronounce supplement (audio)
1
: something that completes or makes an addition
2
: dietary supplement

supplement

2 of 2 transitive verb
sup·​ple·​ment ˈsəp-lə-ˌment How to pronounce supplement (audio)
: to add a supplement to : serve as a supplement for
utilizes … surgery to supplement the traditional treatment—Therapeutic Notes
supplementation
ˌsəp-lə-ˌmen-ˈtā-shən, -mən- How to pronounce supplement (audio)
noun

More from Merriam-Webster on supplement

Nglish: Translation of supplement for Spanish Speakers

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