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

Insurers use savings from reducing waste to lower patient costs and offer supplemental benefits like dental and vision care.

From The Wall Street Journal • Apr. 9, 2026

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

Donaldson told YouTuber Jon Youshaei he anticipates filming supplemental content “educating people on investing and showing them what is a Roth IRA,” for example.

From MarketWatch • Mar. 17, 2026

Ordinarily, he was the strongest member of any group he climbed with, even though he never used supplemental oxygen.

From "Into Thin Air" by Jon Krakauer