SAT TOEFL supplementary Definition Additional to or serving to complete something. Example "The report includes supplementary data in the appendix." Sign in to save SAT Quiz → TOEFL Quiz → ← supplement supplicate → Study tips featuring "supplementary" Let the Argument Reveal Unfamiliar Word Meanings Map Each Word Into a Connected Network Map the Author's Attitude Before Reading Questions Related words SAT antonym SAT abase SAT abdicate SAT abdomen SAT abduction SAT abet SAT abeyance SAT abject SAT abjure SAT ablution SAT abnegate SAT abnormal