1. insidious working or spreading in a hidden and usually injurious way
  2. instance an item of information that is typical of a class or group
  3. instauration the act of starting something for the first time
  4. instancy the quickness of action or occurrence
  5. instar an insect or other arthropod between molts
  6. Anostraca small aquatic crustaceans lacking a carapace: fairy shrimps
  7. anestrous (of lower mammals) not in a state of estrus; not in heat
  8. anestrus applies to nonhuman mammals: a state or interval of sexual inactivity between two periods of estrus
  9. unsaturated used of a compound (especially of carbon) containing atoms sharing more than one valence bond
  10. industrious characterized by hard work and perseverance
  11. unstarred not marked with an asterisk
  12. unstrain cause to feel relaxed
  13. instroke the stroke of an engine piston moving away from the crankshaft
  14. unstrap remove the strap or straps from
  15. instruct impart skills or knowledge to
  16. anoestrous of or relating to anestrus
  17. anoestrus applies to nonhuman mammals: a state or interval of sexual inactivity between two periods of estrus
  18. instigate provoke or stir up
  19. upstairs on a floor above
  20. unstudious not studious