SUPPLEMENTAL Synonyms: 64 Similar and Opposite Words
https://www.merriam-webster.com/thesaurus/supplemental
WebSynonyms for SUPPLEMENTAL: auxiliary, additional, supplementary, accessory, peripheral, makeshift, accessorial, appurtenant; Antonyms of SUPPLEMENTAL: main, principal, chief, basic, primary, fundamental, necessary, prime.
DA: 40 PA: 62 MOZ Rank: 60