1. indefinite article a determiner that indicates nonspecific reference
  2. intrinsic belonging to a thing by its very nature
  3. internet site a computer connected to the internet that maintains a series of web pages on the World Wide Web
  4. interest rate the percentage of a sum of money charged for its use
  5. internal angle the angle inside two adjacent sides of a polygon
  6. definite article a determiner that indicates specificity of reference
  7. intermittent stopping and starting at irregular intervals
  8. interior angle the angle inside two adjacent sides of a polygon
  9. interpenetrate penetrate mutually or be interlocked
  10. interpretable capable of being understood
  11. antiparticle a particle that has the same mass as another particle but has opposite values for its other properties; interaction of a particle and its antiparticle results in annihilation and the production of radiant energy
  12. interstratify arrange rocks in alternating strata
  13. interesting catching or holding your attention
  14. intermediate lying between two extremes in time, space, or state
  15. interestingly in an interesting manner
  16. feature article a special or prominent article in a newspaper or magazine
  17. internal rhyme a rhyme between words in the same line
  18. internal organ a main organ that is situated inside the body
  19. fundamental particle a particle that is less complex than an atom
  20. interstitial of or relating to small spaces between things