1. investigate conduct an inquiry of
  2. inverted being in an upside-down position
  3. invest lay out money or resources in an enterprise
  4. investor someone who commits capital to gain financial returns
  5. investiture the ceremonial promotion of a person to an office or rank
  6. investing the act of investing
  7. invective abusive language used to express blame or censure
  8. intestate having made no valid will or not disposed of by a legal will
  9. investment laying out money or capital in an enterprise
  10. investigator someone who inquires carefully
  11. infest occupy in large numbers or live on a host
  12. untested not yet proved or subjected to testing
  13. unrested not rested or refreshed;
  14. unvented not provided with vents
  15. unfastidious marked by an absence of due or proper care or attention to detail; not concerned with cleanliness
  16. innovative introducing new ideas or creative methods
  17. inventive marked by independence and creativity in thought or action
  18. intestine the part of the alimentary canal between the stomach and the anus
  19. investigatory designed to find information or ascertain facts
  20. manifest clearly revealed to the mind or the senses or judgment