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

Most Advantage enrollees pay no premium besides their Part B outpatient requirement, compared to about $3,000 for traditional Medicare with supplemental “gap” policies.

From The Wall Street Journal • Apr. 9, 2026

The supplemental request probably isn’t pushing stocks lower.

From Barron's • Mar. 19, 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

Almost in unison, my two dentists advised against that because Medicare supplemental plans can be so limited.

From Los Angeles Times • Feb. 28, 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