supplemental

American  

[suhp-luh-men-tl] / ˌsʌp ləˈmɛn tl /

adjective

1. supplementary.

2. nonscheduled.

3. (of a pleading, an affidavit, etc.) added to furnish what is lacking or missing.

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noun

1. anything that is supplemental.

   supplementals attached to the bill in committee.

Other Word Forms

• nonsupplemental adjective
• nonsupplementally adverb
• presupplemental adjective
• supplementally adverb
• unsupplemental adjective

Etymology

Origin of supplemental

First recorded in 1595–1605; supplement + -al ¹

Explanation

You can use the adjective supplemental to describe something extra. You could volunteer to donate your collection of markers and colored pencils to a local school that needs supplemental art supplies. Something that's supplemental is added when there's a lack or deficiency. You might feed the runt from a litter of puppies supplemental milk because he can't get enough from his mother. Teachers are famous for assigning supplemental reading to round out the information in a textbook. Supplemental comes from the Latin supplementum, "added to supply a deficiency."

Example Sentences

Will the supplemental start to reduce that risk by expanding ships, aircraft and personnel—all expensive?

From The Wall Street Journal • Mar. 23, 2026

Another $200 billion in supplemental spending, passed before Sept. 30, would push fiscal year 2026 spending to about $1.2 trillion.

From Barron's • Mar. 19, 2026

You will have to pay premiums — Medicare Part B, supplemental insurance or a Medicare Advantage plan, and prescription-drug coverage.

From MarketWatch • Mar. 12, 2026

Instead, Truman sent a message to the Hill justifying the use of U.S. force, and Congress approved supplemental funding for Korea.

From The Wall Street Journal • Mar. 10, 2026

However, without supplemental oxygen, I moved more slowly, and I had to stop and rest more often.

From "Into Thin Air" by Jon Krakauer