supplemental

adjective

sup·​ple·​men·​tal ˌsə-plə-ˈmen-tᵊl 

1

: serving to supplement

2

: nonscheduled

a supplemental airline

supplemental noun

Synonyms of supplemental

• auxiliary
• additional
• supplementary
• accessory
• peripheral

Examples of supplemental in a Sentence

She receives a supplemental income every month from the government.

the new program will provide supplemental health insurance to thousands of workers

Recent Examples on the Web

To promote bushy growth, place parsley in a sunny windowsill or use supplemental lighting. —Brandee Gruener, Southern Living, 3 Feb. 2026

Those funds could then be used for tutoring, tuition, supplemental classes, books, online educational materials, standardized testing fees, dual enrollment courses, special-education services and more. —Chicago Tribune, 3 Feb. 2026

When combined with a Medicare supplemental plan, which the city has always provided to Medicare-eligible retired municipal workers, costs are minimal. —Marianne Pizzitola, New York Daily News, 31 Jan. 2026

Because of this, these plants don’t need much supplemental lighting. —Rachel Gillett, Martha Stewart, 31 Jan. 2026

Word History

Etymology

supplement entry 1 + -al entry 1

First Known Use

1605, in the meaning defined at sense 1

Rhymes for supplemental

• accidental
• compartmental
• continental
• detrimental
• elemental
• fundamental
• governmental
• incidental
• incremental
• instrumental
• interdental
• monumental

Medical Definition

supplemental

adjective

sup·​ple·​men·​tal ˌsəp-lə-ˈment-ᵊl 

: serving to supplement : supplementary

Legal Definition

supplemental

adjective

sup·​ple·​men·​tal ˌsə-plə-ˈment-ᵊl 

: serving to complete or make an addition

supplemental appropriations

specifically : of, relating to, or being a supplemental pleading

supplemental noun