[noun suhp-luh-muhnt; verb suhp-luh-ment]


something added to complete a thing, supply a deficiency, or reinforce or extend a whole.
a part added to a book, document, etc., to supply additional or later information, correct errors, or the like.
a part, usually of special character, issued as an additional feature of a newspaper or other periodical.
Geometry. the quantity by which an angle or an arc falls short of 180° or a semicircle.

verb (used with object)

Origin of supplement

1350–1400; Middle English < Latin supplēmentum that by which anything is made full, equivalent to sup- sup- + plē- (stem of plēre to fill; see full1) + -mentum -ment
Related formssup·ple·ment·er, nounun·sup·ple·ment·ed, adjectivewell-sup·ple·ment·ed, adjective
Can be confusedappendix index supplement (see synonym study at appendix)complement supplement (see synonym study at complement)

Synonyms for supplement Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

Examples from the Web for supplementing

Contemporary Examples of supplementing

Historical Examples of supplementing

  • "Too slowly, since swords and pikes have to be supplementing its blade," said Gilbert.

    The Countess of Charny

    Alexandre Dumas (pere)

  • Two passages from his diary, the second supplementing the first, supply the picture.


    Francis Henry Gribble

  • I shall only be supplementing what you told in your letters, Laura.

    Three Comedies

    Bjrnstjerne M. Bjrnson

  • Miss Ellsling, on the stage, seemed to be supplementing this remark.

    Harlequin and Columbine

    Booth Tarkington

  • The other boy joined in at intervals, supplementing my remarks.

    Across the Prairie in a Motor Caravan

    Frances Halton Eva Hasell

British Dictionary definitions for supplementing


noun (ˈsʌplɪmənt)

an addition designed to complete, make up for a deficiency, etc
a section appended to a publication to supply further information, correct errors, etc
a magazine or section inserted into a newspaper or periodical, such as one with colour photographs issued every week
  1. either of a pair of angles whose sum is 180°
  2. an arc of a circle that when added to another arc forms a semicircleAbbreviation: sup, supp

verb (ˈsʌplɪˌmɛnt)

(tr) to provide a supplement to, esp in order to remedy a deficiency
Derived Formssupplementation, nounsupplementer, noun

Word Origin for supplement

C14: from Latin supplēmentum, from supplēre to supply 1
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Word Origin and History for supplementing



late 14c., from Latin supplementum "something added to supply a deficiency," from supplere (see supply (v.)).



1829, from supplement (n.). Related: Supplemented; supplementing.

Online Etymology Dictionary, © 2010 Douglas Harper