1. unnecessary not needed
  2. incessant uninterrupted in time and indefinitely long continuing
  3. genus Herpestes mongooses
  4. necessary absolutely essential
  5. exacerbate make worse
  6. unnecessarily without any necessity
  7. unsurpassed not capable of being improved on
  8. genus Syrrhaptes a genus of Pteroclididae
  9. Yersinia pestis a bacillus bacterium that causes the plague
  10. unseasonableness being at an inappropriate time
  11. unsociableness an unsociable disposition
  12. genus Sarcocystis chief genus of the order Sarcosporidia
  13. unsuspicious not suspicious
  14. Anthoceropsida hornworts: in some classification systems included in the class Hepaticopsida
  15. genus Cerastes horned vipers
  16. incessantness the quality of something that continues without end or interruption
  17. Insessores a bird with feet adapted for perching
  18. genus Sarcoptes type genus of the family Sarcoptidae: itch mites
  19. Erinaceus europeaeus small nocturnal Old World mammal covered with both hair and protective spines
  20. answerableness responsibility to someone or for some activity