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

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

With the population of college-goers shrinking in coming years, higher-education institutions are fighting over a smaller pie—and supplemental essays can deter applicants.

From The Wall Street Journal • Jul. 10, 2026

Kathleen Keesey, who recently graduated from high school near Denver, wrote 29 supplemental essays for admission, plus dozens more for scholarships and honors programs.

From The Wall Street Journal • Jul. 10, 2026

About 43% of people enrolled in traditional Medicare have Medigap supplemental insurance, according to health policy research firm KFF.

From MarketWatch • Jun. 27, 2026

A cost cap would save enrollees an average of about $1,200 a year in direct savings and reductions in their Medigap supplemental premiums, according to a study by Brown University.

From MarketWatch • Jun. 27, 2026

Namba had perished on the South Col, just twenty minutes from shelter, assigned to a summit party, and on May 16 he reached the top without supplemental oxygen.

From "Into Thin Air" by Jon Krakauer