Used or held in reserve
(Grammar) Relating to an auxiliary verb.
For use during emergencies:
Second or lower in rank or importance; not primary:
Of, for, or functioning as a standby
Being, or having the nature of, a reserve or reserves
Find another word for supplementary. In this page you can discover 14 synonyms, antonyms, idiomatic expressions, and related words for supplementary, like: completing, backup, increase, extra, supplemental, auxiliary, emergency, secondary, standby, subsidiary and additional.