1. persistent stubbornly unyielding
  2. persistence continuing or repeating behavior
  3. presentiment a feeling of evil to come
  4. precipitate bring about abruptly
  5. appreciate be fully aware of; realize fully
  6. precedent an example that is used to justify similar occurrences
  7. time frame a time period during which something occurs or is expected to occur
  8. overseas telegram a telegram sent abroad
  9. precious metal any of the less common and valuable metals often used to make coins or jewelry
  10. Brazos River a river that rises in Mexico and flows across Texas into the Gulf of Mexico
  11. precision rifle an extremely powerful rifle developed for the military
  12. picture frame a framework in which a picture is mounted
  13. paradise tree medium to large tree of tropical North and South America having odd-pinnate leaves and long panicles of small pale yellow flowers followed by scarlet fruits
  14. precise sharply exact or accurate or delimited
  15. power system a system of high tension cables by which electrical power is distributed throughout a region
  16. ecosystem organisms interacting with their physical environment
  17. debris storm the sudden spread of dust and debris from a collapsing building
  18. processing time the time it takes to complete a prescribed procedure
  19. precedence status established in order of importance or urgency
  20. precipitator removes dust particles from gases by electrostatic precipitation