SUPPLEMENTARY Synonyms: 64 Similar and Opposite Words

supplementary

adjective

ˌsə-plə-ˈmen-tə-rē

Definition of supplementary

as in auxiliary

available to supply something extra when needed the teacher's edition of the textbook comes with a lot of supplementary material

Synonyms & Similar Words

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Antonyms & Near Antonyms

as in complementary

related to each other in such a way that one completes the other regards theology and philosophy as supplementary fields of study

Synonyms & Similar Words

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 supplementary Pills and gel capsules Many people incorporate elderberries into their diets as supplementary pills or lozenges. — Bestreviews, Chicago Tribune, 4 Sep. 2026 The sleeping surface measures 82 inches (208 cm) long and is widened via slim supplementary cushions to 57 inches (145 cm) at the head by the doors, tapering to 50 inches (127 cm) at the foot between the wheel wells. — New Atlas, 18 Aug. 2026 In 2024, Purja became the fastest person to summit all 14 of the peaks without supplementary oxygen. — Lex Harvey, CNN Money, 31 July 2026 Coverage is provided by Employees’ Health Insurance and National Health Insurance schemes; private insurance only plays a supplementary role. — Runchana Pongsaparn, Fortune, 31 July 2026 See All Example Sentences for supplementary

Recent Examples of Synonyms for supplementary

Adjective

Storyteller Overland Powering up the sockets and appliances, the Gear Mode packs in 4+ kWh of Lithionics batteries that send power through a 2,000-W inverter and charge while driving through a high-output auxiliary alternator.

— New Atlas, New Atlas, 15 Oct. 2026
The cabin also has been outfitted with brand’s Smooth Pack amenities, which include ambient lighting and auxiliary outlets.

— Bryan Hood, Robb Report, 14 Oct. 2026

Definition of auxiliary

Adjective

Silver Mirror recommends three Volmira visits, one a month, followed by three months of complementary facials, then repeating the cycle.

— Kathryn Hopkins, Footwear News, 14 Oct. 2026
Combining several complementary signals could deliver greater benefits.

— Mike McRae October 09, New Atlas, 10 Oct. 2026

Definition of complementary

Adjective

After confirming that the line from Exeter that ran through the village of Starcross didn’t open until the end of May, 1846, Cade and his team turned to the schedule for additional clues.

— Mike McRae October 15, New Atlas, 16 Oct. 2026
Darrell Alexander, who runs composer agency Cool Music, sees working as an additional composer as the best entry point for anyone starting out.

— Ben Croll, Variety, 16 Oct. 2026

Definition of additional

Adjective

Ideally, a reciprocal halt in long-range air and missile attacks could then be replicated across other sectors—maritime, commercial, and transportation—thus forming the basis of a broader aerial cease-fire.

— Eric Ciaramella, Foreign Affairs, 14 Oct. 2026
The Houthis now claim the right to impose reciprocal restrictions on Saudi Arabia, particularly by targeting its ports and oil-exporting infrastructure.

— Laurent Bonnefoy, The Conversation, 14 Oct. 2026

Definition of reciprocal

Adjective

Aside from California, the other states with the highest housing cost impact on the supplemental poverty measure are Colorado, Connecticut, Hawaii, Maryland, Massachusetts, New Hampshire, New Jersey, New York and Washington.

— Graham Womack, Sacbee.com, 15 Oct. 2026
High-profile essays like hers are reframing lobular carcinoma from clinical footnote to mainstream concern, and that reframing tends to drive demand for supplemental screening.

— Samantha Agate, Kansas City Star, 14 Oct. 2026

Definition of supplemental

Adjective

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
The accessory lineup has become fairly standard across brands.

— Lauren Jarvis-Gibson, Charlotte Observer, 1 Oct. 2026

Definition of accessory

Browse Nearby Words

supplemental

supplementary

supplementation

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“Supplementary.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/supplementary. Accessed 20 Oct. 2026.

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Synonyms of supplementary

adjective

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