SUPPLEMENTAL Synonyms: 64 Similar and Opposite Words

supplemental

adjective

ˌsə-plə-ˈmen-tᵊl

Definition of supplemental

as in auxiliary

available to supply something extra when needed the new program will provide supplemental health insurance to thousands of workers

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Antonyms & Near Antonyms

as in supplementary

related to each other in such a way that one completes the other an astronomer who regards science and religion not as antithetical but as supplemental belief systems

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Antonyms & Near Antonyms

Example Sentences

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.

Recent Examples of supplemental Douthat himself describes this project as speculative historical fiction, and the data-dumping, supplemental world-building documents are certainly dense with history and archangels. — James Folta, Literary Hub, 14 Oct. 2026 In Sun Valley, Idaho, guests are privy to an encounter with mountaineer Ed Viesturs, known for climbing all 14 of the world’s 8,000-meter peaks without supplemental oxygen. — Sofia Celeste, Footwear News, 13 Oct. 2026 In December 2021, however, the DOL under the Biden administration issued a supplemental statement, contending that most plan fiduciaries were not suited to evaluate alternative investments, given their complexity and high risk. — Cheryl Winokur Munk, CNBC, 10 Oct. 2026 In addition, they were each charged with grand theft of Siira’s supplemental security income. — Idaho Statesman, 9 Oct. 2026 See All Example Sentences for supplemental

Recent Examples of Synonyms for supplemental

Adjective

According to Boeing, the aircraft offers 365 nautical miles more range than competing aircraft without auxiliary fuel tanks.

— Neetika Walter, Interesting Engineering, 21 Oct. 2026
The band has also added various auxiliary members for albums and live performances.

— Paul Grein, Billboard, 19 Oct. 2026

Definition of auxiliary

Adjective

Like other clubs, Gollancz expanded its service to additional, supplementary and educational texts, all optional.

— Literary Hub, Literary Hub, 20 Oct. 2026
The space is warm and lo-fi—Polaroids of friends and a handwritten lineup of the day’s specials (which can be added at a supplementary cost) are stuck to a noticeboard—but the food is sharp and assured.

— Helen Rosner, New Yorker, 11 Oct. 2026

Definition of supplementary

Adjective

The increase also reflects a few additional states that expanded their early voting opportunities and ones that made more of their data available since the last midterms.

— Arkansas Online, Arkansas Online, 23 Oct. 2026
The Marlins would try to extend their top young players who are approaching their arbitration years — or are already in their arbitration years — potentially taking on some additional money early in multiyear contracts.

— Barry Jackson, Miami Herald, 22 Oct. 2026

Definition of additional

Adjective

Jayaprakash argues Blacksmith is complementary to what the AI model companies do, because better models mean more code to check.

— Beatrice Nolan, Fortune, 21 Oct. 2026
Even as new equipment and materials transformed the room, the principle of planning storage, appliances, and work surfaces as a continuous, complementary whole endured.

— Tara Anne Dalbow, Architectural Digest, 21 Oct. 2026

Definition of complementary

Adjective

The study looked at converting existing single-family homes into multi-unit residences, standalone accessory dwelling units and multi-unit buildings.

— Cam'ron Hardy, Chicago Tribune, 18 Oct. 2026
These superficial veins are not critical to circulation — they’re considered accessory veins, which the body uses mainly for volume storage and temperature regulation, Stoughton said.

— Erica Sloan, Washington Post, 10 Oct. 2026

Definition of accessory

Adjective

When viewers focus on one gear, the other, as seen through peripheral vision, appears to spin faster — though both are moving at the same speed.

— Margaret Hetherman, Washington Post, 27 Oct. 2026
But because of my peripheral association with the Exorcist reissue, people are now taking my phone calls.

— David Fear, Rolling Stone, 18 Oct. 2026

Definition of peripheral

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supplement

supplemental

supplementary

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Style

“Supplemental.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/supplemental. Accessed 28 Oct. 2026.

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Synonyms of supplemental

adjective

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