supplement

American  

[suhp-luh-muhnt, suhp-luh-ment] / ˈsʌp lə mənt, ˈsʌp ləˌmɛnt /

noun

• supplements
  plural

1. something added to complete a thing, supply a deficiency, or reinforce or extend a whole.

2. a part added to a book, document, etc., to supply additional or later information, correct errors, or the like.

   Synonyms:

   postscript, epilogue, addendum

3. a part, usually of special character, issued as an additional feature of a newspaper or other periodical.

4. Geometry. the quantity by which an angle or an arc falls short of 180° or a semicircle.

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verb (used with object)

• supplements,
  present (3rd person singular)
• supplemented,
  past participle,  past
• supplementing
  present participle

1. to complete, add to, or extend by a supplement.

2. to form a supplement or addition to.

3. to supply (a deficiency).

supplement British  

noun

1. an addition designed to complete, make up for a deficiency, etc

2. a section appended to a publication to supply further information, correct errors, etc

3. a magazine or section inserted into a newspaper or periodical, such as one with colour photographs issued every week

4. geometry

   1. either of a pair of angles whose sum is 180°

   2. Abbreviation: sup, supp. an arc of a circle that when added to another arc forms a semicircle

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verb

1. (tr) to provide a supplement to, esp in order to remedy a deficiency

Usage

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.  

Synonym Usage

See appendix. See complement.

Other Word Forms

Derived Forms

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

Inflected Forms

Nouns

• supplements
  plural

Participles

• supplementing
  present
• supplemented
  past

Conjugated Forms

Present

• supplement
  simple
• supplements
  simple
• have supplemented
  perfect
• has supplemented
  perfect
• am supplementing
  progressive
• are supplementing
  progressive
• is supplementing
  progressive
• have been supplementing
  perfect progressive
• has been supplementing
  perfect progressive

Past

• supplemented
  simple
• had supplemented
  perfect
• was supplementing
  progressive
• were supplementing
  progressive
• had been supplementing
  perfect progressive

Future

• will supplement
  simple
• will have supplemented
  perfect
• will be supplementing
  progressive
• will have been supplementing
  perfect progressive

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Etymology

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 full ¹) + -mentum -ment

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Explanation

A supplement is something added to something else. Nutritional supplements add vitamins and minerals to the ones already included in the food you eat. If a zombie army wants to increase its ranks but is running out of bodies, it might supplement its troops with mummies. If the zombies put out their manifesto and then realize they left out an important point, they might supplement the manifesto with a press release. That press release could also be referred to as a supplement.

Example Sentences

See Examples For:

supplement supplements supplemented supplementing

While American workers have long managed their own retirement portfolios to supplement a baseline Social Security check, continental Europeans were promised a comprehensive, state-guaranteed income for life.

From The Wall Street Journal ● Nov. 1, 2026

Doctors don't routinely offer blood tests to check for vitamin D deficiency, but will offer a supplement if a patient is concerned they might be high risk.

From BBC ● Oct. 30, 2026

However, the inulin supplement used in this trial was not a GLP-1 medication.

From Science Daily ● Oct. 28, 2026

The few hundred dollars a month credited to a card she could use at supermarkets allowed her to supplement her modest retirement funds and keep her family afloat.

From Barron's ● Oct. 28, 2026

We were so poor my mother took three quarters of my paycheck every week to supplement the family income.

From "Made You Up" by Francesca Zappia

I’ll take my supplements and I’ll pull up the shade on my terrace and watch the sunrise.

From Los Angeles Times ● Oct. 30, 2026

Vitamin D can come from our diet, in foods such as oily fish and meat, or supplements.

From BBC ● Oct. 30, 2026

Pre-Covid data, when adjusted for inflation, show that wage compensation—total wages and salaries plus supplements such as employer contributions to pensions and savings plans—closely tracked productivity gains.

From The Wall Street Journal ● Oct. 29, 2026

But a new study suggests that getting more omega-3s into the brain through supplements may not provide the protection many people expect.

From Science Daily ● Oct. 22, 2026

She stopped to browse through the shelf of role-playing game supplements.

From "Ready Player One: A Novel" by Ernest Cline

When researchers supplemented the animals' diets with LPC70, several of these effects were reduced.

From Science Daily ● Oct. 18, 2026

But with their capabilities supplemented by human teleoperators, Tau’s robots climbed with deliberate accuracy, albeit a little slowly.

From MarketWatch ● Oct. 16, 2026

The witches are thus visible manifestations of internal malevolent urges, and the 12 dancer witches who supplemented the large singing chorus of hags appeared throughout the evening—observing, slipping through walls, and egging the protagonists on.

From The Wall Street Journal ● Sep. 24, 2026

And so, when they ended up in front of miraculous testimonials of healing, often supplemented by A.I.-generated photos or videos, they took it seriously.

From Slate ● Sep. 22, 2026

Now that the trip was delayed by a minimum of several months, the ship’s stores had to be supplemented with fresh meat.

From "Shipwreck at the Bottom of the World" by Jennifer Armstrong

In January, Boeing unveiled a new MAX production line in Everett, Washington, supplementing output for a plane that had previously been assembled exclusively in Renton, Washington.

From Barron's ● Oct. 20, 2026

They also need to understand whether altering Menin or supplementing D-serine could produce unintended effects.

From Science Daily ● Sep. 18, 2026

The ratio was changed a bit—ground ops were supplementing the air war, not the other way around; but still the ground ops were necessary.

From Slate ● Jul. 30, 2026

“Medicaid compliant annuities give fixed monthly payments to the well spouse, supplementing their income or Social Security benefits,” it says.

From MarketWatch ● Mar. 26, 2026

It was also becoming apparent that the possibility of supplementing their food rations with game, such as the tapir, looked bleak.

From "Death on the River of Doubt" by Samantha Seiple

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Related Words

• augment
• build up
• buttress
• complement
• enhance
• enrich
• fill out
• fortify
• improve
• reinforce
• strengthen
• subsidize

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