supplementary

American  

[suhp-luh-men-tuh-ree] / ˌsʌp ləˈmɛn tə ri /

adjective

1. Also of the nature of or forming a supplement; additional.

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noun

plural

supplementaries

1. a person or thing that is supplementary.

supplementary British  

/ -trɪ, ˌsʌplɪˈmɛntərɪ /

adjective

1. Also (less commonly): supplemental.  forming or acting as a supplement

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noun

1. a person or thing that is a supplement

Other Word Forms

• nonsupplementary adjective
• presupplementary adjective
• supplementarily adverb
• unsupplementary adjective

Etymology

Origin of supplementary

First recorded in 1660–70; supplement + -ary

Example Sentences

And South Korea said it will roll out a $17 billion "wartime" supplementary budget and expand fuel tax cuts.

From Barron's • Mar. 27, 2026

Oil and gas firms operating in the North Sea pay a 30% corporation tax on their profits and a supplementary 10% rate on top of that.

From BBC • Jan. 21, 2026

“If the total amount for JGB issuance is to grow further after this fiscal year’s supplementary budget, there will be the risk of further rises” in JGB yields, the rates strategist says.

From The Wall Street Journal • Dec. 22, 2025

Meanwhile, banks are enjoying a regulatory tailwind under the enhanced supplementary leverage ratio for the biggest banks now in the works.

From MarketWatch • Nov. 11, 2025

This setback had not put a damper on his Himalayan career, however: he’d gone on to climb K2, Lhotse, Cho Oyu, Ama Dablam, and, in 1993, Everest without supplementary oxygen.

From "Into Thin Air" by Jon Krakauer

Related Words

• ancillary
• auxiliary
• increased