[ noun suhp-luh-muhnt; verb suhp-luh-ment ]
/ noun ˈsʌp lə mənt; verb ˈsʌp ləˌmɛnt /
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See synonyms for: supplement / supplemented / supplementing / supplements on Thesaurus.com

something added to complete a thing, supply a deficiency, or reinforce or extend a whole.
a part added to a book, document, etc., to supply additional or later information, correct errors, or the like.
a part, usually of special character, issued as an additional feature of a newspaper or other periodical.
Geometry. the quantity by which an angle or an arc falls short of 180° or a semicircle.
verb (used with object)
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Origin of supplement

First recorded in 1350–1400; Middle English, from Latin supplēmentum “that by which anything is made full,” equivalent to sup-sup- + plē- (stem of plēre “to fill”; see full1) + -mentum-ment

synonym study for supplement

2. See appendix. 5. See complement.


sup·ple·ment·er, nounun·sup·ple·ment·ed, adjectivewell-sup·ple·ment·ed, adjective


1. appendix, index, supplement (see synonym study at appendix)2. complement, supplement (see synonym study at complement)
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2022


What does supplement mean?

A supplement is an addition to something that completes it or makes up for a shortcoming, as in He takes vitamin supplements to make up for his vitamin C deficiency.

A supplement is also an addition to a book that provides important information or corrects errors. In this sense, supplement can be confused with the words appendix and index. An appendix gives additional information, such as charts and graphs, but the book or document would be considered complete without it. An index is an alphabetical list of names or topics with page numbers that helps you find something specific in the book, such as all the references to John Wilkes Booth in a biography of Abraham Lincoln.

As a verb, supplement means to add to something, as in Tameka sold paintings to supplement her income.

In this sense, supplement can be confused with the word complement. Both words mean to add something, but to complement means to add something to make up for a missing piece or element, while to supplement is to add extra information.

Example: The company built a new roller coaster to supplement its original roller coaster, which always has a long line.  

Where does supplement come from?

The first records of supplement come from around 1350. It comes from the Latin noun supplēmentum, meaning “that by which anything is made full.” A supplement is often an addition that makes up for something that is lacking.

The word supplement is commonly used to specifically refer to pills or other substances that are designed to provide nutrients that might be missing in your diet. In the United States, the Food and Drug Association carefully regulates these products and ensures that they are not dangerous or don’t make false health claims. Often, you would take these dietary supplements to make up for vitamins or essential nutrients you’re not getting normally, such as due to dietary restrictions.

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What are some other forms related to supplement?

  • supplementer (noun)
  • supplementation (noun)
  • unsupplemented (adjective)
  • well-supplemented (adjective)

What are some synonyms for supplement?

What are some words that share a root or word element with supplement

What are some words that often get used in discussing supplement?

What are some words supplement may be commonly confused with?

How is supplement used in real life?

Supplement is a common word that is often used in “dietary supplements.”

Try using supplement!

Is supplement used correctly in the following sentence?

Natasha added some flowers and decorations to the room to supplement its beauty.

How to use supplement in a sentence

British Dictionary definitions for supplement


noun (ˈsʌplɪmənt)
an addition designed to complete, make up for a deficiency, etc
a section appended to a publication to supply further information, correct errors, etc
a magazine or section inserted into a newspaper or periodical, such as one with colour photographs issued every week
  1. either of a pair of angles whose sum is 180°
  2. an arc of a circle that when added to another arc forms a semicircleAbbreviation: sup, supp
verb (ˈsʌplɪˌmɛnt)
(tr) to provide a supplement to, esp in order to remedy a deficiency

Derived forms of supplement

supplementation, nounsupplementer, noun

Word Origin for supplement

C14: from Latin supplēmentum, from supplēre to supply 1
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