Supererogatory \Su`per*e*rog"a*to*ry\, a. Performed to an extent not enjoined, or not required, by duty or necessity; as, supererogatory services. --Howell. [1913 Webster]

Source: The Collaborative International Dictionary of English v.0.48
 

25 Moby Thesaurus words for "supererogatory": de trop, dispensable, excess, expendable, expletive, gratuitous, in excess, needless, nonessential, pleonastic, prolix, redundant, spare, superfluous, supernumerary, tautologic, tautologous, to spare, unasked, uncalled-for, unessential, unnecessary, unneeded, verbose, wanton

Source: Moby Thesaurus II by Grady Ward, 1.0
 

supererogatory adj : more than is needed, desired, or required; "trying to lose excess weight"; "found some extra change lying on the dresser"; "yet another book on heraldry might be thought redundant"; "skills made redundant by technological advance"; "sleeping in the spare room"; "supernumerary ornamentation"; "it was supererogatory of her to gloat"; "delete superfluous (or unnecessary) words"; "extra ribs as well as other supernumerary internal parts"; "surplus cheese distributed to the needy" [syn: excess, extra, redundant, spare, superfluous, supernumerary, surplus]

Source: WordNet (r) 2.0
 

Supererogatory \Su`per*e*rog"a*to*ry\, a. Performed to an extent not enjoined, or not required, by duty or necessity; as, supererogatory services. --Howell.

Source: Webster's Revised Unabridged Dictionary (1913)