supplement
Americannoun
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supplements
plural
-
something added to complete a thing, supply a deficiency, or reinforce or extend a whole.
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a part added to a book, document, etc., to supply additional or later information, correct errors, or the like.
- Synonyms:
- postscript, epilogue, addendum
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a part, usually of special character, issued as an additional feature of a newspaper or other periodical.
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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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supplements,
present (3rd person singular)
-
supplemented,
past participle, past
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supplementing
present participle
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to complete, add to, or extend by a supplement.
-
to form a supplement or addition to.
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to supply (a deficiency).
noun
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an addition designed to complete, make up for a deficiency, etc
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a section appended to a publication to supply further information, correct errors, etc
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a magazine or section inserted into a newspaper or periodical, such as one with colour photographs issued every week
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geometry
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either of a pair of angles whose sum is 180°
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Abbreviation: sup, supp. an arc of a circle that when added to another arc forms a semicircle
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verb
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
Inflected Forms
Nouns
Participles
Conjugated Forms
Present
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supplementsimple
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supplementssimple
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have supplementedperfect
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has supplementedperfect
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am supplementingprogressive
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are supplementingprogressive
-
is supplementingprogressive
-
have been supplementingperfect progressive
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has been supplementingperfect progressive
Past
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supplementedsimple
-
had supplementedperfect
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was supplementingprogressive
-
were supplementingprogressive
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had been supplementingperfect progressive
Future
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
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.
Vocabulary lists containing supplement
Richard Nixon's "Checkers" Speech (1952)
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Nutrition - Introductory
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Nutrition - Middle School
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Example Sentences
Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.
See Examples For:
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
The researchers found that participants taking inulin had increased levels of butyrate, suggesting that the supplement was influencing activity within the gut microbiome.
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
Exploring about in his coat pockets, Rick found his creased, much-studied copy of Sidney's Animal & Fowl Catalogue January supplement.
From "Do Androids Dream of Electric Sheep?" by Philip K. Dick
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
Before evaluating whether the supplements improved brain health, researchers needed to answer a fundamental question: Were the omega-3 fatty acids actually reaching the brain?
From Science Daily ● Oct. 22, 2026
“The vet didn’t know what to make of it. He told me to keep giving him the supplements and the vitamins, but that basically he’s a medical miracle.”
From "It’s Kind of a Funny Story" by Ned Vizzini
When researchers supplemented the animals' diets with LPC70, several of these effects were reduced.
From Science Daily ● Oct. 18, 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
Over the years, my mother and I have supplemented his income.
From MarketWatch ● Sep. 10, 2026
Voting-rights groups supplemented a parallel suit to challenge the rule as well.
From Slate ● Aug. 31, 2026
Freddie’s janitor duties at the department store were supplemented by his function as a messenger and package deliverer.
From "Song of Solomon" by Toni Morrison
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
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
Rather than replacing existing recommendations, Dr. Macdonald suggests supplementing them with guidance focused on what he calls "optimal health outcomes."
From Science Daily ● Jun. 23, 2026
Proponents said it can elevate instruction, narrow the digital divide, help pupils with language barriers and other needs—while often supplementing, not replacing, core curriculum.
From The Wall Street Journal ● Jun. 21, 2026
The mighty dinos stood in military formation, each with additional armor supplementing its already fierce horned head shield and thick hide.
From "Dactyl Hill Squad" by Daniel José Older
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