supererogatory

1. It was supererogatory for her to gloat ( Mary McCarthy)
   她也在一旁幸灾乐祸地看得出神，真是多余（玛丽麦卡锡）
2. Any higher standard of care that the researchers or sponsors are able to provide is supererogatory: that is, morally praiseworthy, but not obligatory.
   这样，研究者和试验发起人给予的任何更高层次的关心都是额外的：也就是说，在道德上值得称颂，但并不是义务的。

adj

1. more than is needed, desired, or required
   1. trying to lose excess weight
   2. found some extra change lying on the dresser
   3. yet another book on heraldry might be thought redundant
   4. skills made redundant by technological advance
   5. sleeping in the spare room
   6. supernumerary ornamentation
   7. it was supererogatory of her to gloat
   8. delete superfluous (or unnecessary) words
   9. extra ribs as well as other supernumerary internal parts
   10. surplus cheese distributed to the needy

   Synonym:    excessextraredundantsparesuperfluoussupernumerarysurplus