41 synonyms for unnecessary such as bounteous, abundant, and ample. Unnecessary is an adjective, and its antonyms are essential and necessary.
Abundant, Ample, Bounteous, Copious, Dispensable, Excess, Excessive, Extensive, Extravagant, Frivolous, Galore, Gratuitous, Inessential, Irrelevant, Lavish, Lush, Nonessential, Outlandish, Overabundant, Overflowing, Overkill, Plentiful, Pointless, Profuse, Redundant, Supererogatory, Superfluous, Surplus, Trivial, Uncalled-for, Unjustified, Unmerited, Unnecessary, Unneeded, Unrequested, Unrequired, Unwanted, Unwarranted, Useless, and Wasteful.