[ noun suhp-luh-muhnt; verb suhp-luh-ment ]
/ noun ˈsʌp lə mənt; verb ˈsʌp ləˌmɛnt /
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See synonyms for: supplement / supplemented / supplementing / supplements on Thesaurus.com


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)



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Origin of supplement

First recorded in 1350–1400; Middle English, from Latin supplēmentum “that by which anything is made full,” equivalent to sup-sup- + plē- (stem of plēre “to fill”; see full1) + -mentum-ment
2. See appendix. 5. See complement.
sup·ple·ment·er, nounun·sup·ple·ment·ed, adjectivewell-sup·ple·ment·ed, adjective
1. appendix, index, supplement (see synonym study at appendix)2. complement, supplement (see synonym study at complement)
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2021

British Dictionary definitions for supplement


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
supplementation, nounsupplementer, noun
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
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