indispensable Antonyms

dispensable subordinate tertiary trifling trivial unessential unsubstantial useless valueless tautologic surplus supplementary substituent superaddition superficial superfluous superimposed supernumerary supervenient supplanter worthless unimportant irrelevant de trop disorganic non-essential unneeded overpayment spare part stoppable unrequested nonmandatory meter maid unnecessary backup procedural fill-in avertable locum pinch hitter meaningless less important slight accessorial discretionary disposable elective evitable extrinsic frivolous