supplementary

adjective

sup·​ple·​men·​ta·​ry ˌsə-plə-ˈmen-tə-rē 

-ˈmen-trē

1

: added or serving as a supplement : additional

supplementary reading

2

: being or relating to a supplement (see supplement entry 1 sense 3) or a supplementary angle

Synonyms of supplementary

• auxiliary
• additional
• supplemental
• accessory

Examples of supplementary in a Sentence

a list of supplementary material for the class

the teacher's edition of the textbook comes with a lot of supplementary material

Recent Examples on the Web

Others are treated as supplementary. — Literary Hub, 26 June 2026

The public evidence—exhibits, hearings, et cetera—was piled into the supplementary volumes. — Kaitlyn Tiffany, The Atlantic, 20 June 2026

For the dependency support test, basic and supplementary Medicare benefits are not counted as support. — Kelly Phillips Erb, Forbes.com, 20 June 2026

The council is also considering a supplementary moratorium on battery energy storage sites. — Ilana Arougheti, Kansas City Star, 25 June 2026

Word History

Etymology

supplement entry 1 + -ary entry 2

First Known Use

1667, in the meaning defined at sense 1

Phrases Containing supplementary

• supplementary angle

Rhymes for supplementary

• alimentary
• complimentary
• documentary
• parliamentary
• rudimentary
• sedimentary
• testamentary
• integumentary
• uncomplimentary
• unparliamentary
• interparliamentary
• metasedimentary

Kids Definition

supplementary

adjective

sup·​ple·​men·​ta·​ry ˌsəp-lə-ˈment-ə-rē 

-ˈmen-trē

1

: added as a supplement : additional

2

: being or relating to a supplement or a supplementary angle

Medical Definition

supplementary

adjective

sup·​ple·​men·​ta·​ry ˌsəp-lə-ˈment-ə-rē, -ˈmen-trē 

: added or serving as a supplement

supplementary vitamins

Legal Definition

supplementary

adjective

sup·​ple·​men·​ta·​ry ˌsə-plə-ˈmen-tə-rē, -trē 

: added or serving as a supplement