1. principal main or most important
  2. principle a basic generalization that is accepted as true
  3. Principality of Andorra a small republic in the eastern Pyrenees between Spain and France
  4. principal axis a line that passes through the center of curvature of a lens so that light is neither reflected nor refracted
  5. principal diagonal the diagonal of a square matrix running from the upper left entry to the lower right entry
  6. Principality of Monaco a constitutional monarchy in a tiny enclave on the French Riviera
  7. Princess of Wales English aristocrat who was the first wife of Prince Charles
  8. princess feather annual with broadly ovate leaves and slender drooping spikes of crimson flowers; southeastern Asia and Australia; naturalized in North America
  9. principal investigator the scientist in charge of an experiment or research project
  10. principality territory ruled by a prince
  11. printer's devil an apprentice in a printing establishment
  12. Prunus padus small European cherry tree closely resembling the American chokecherry
  13. Princess Diana English aristocrat who was the first wife of Prince Charles
  14. prince's-feather annual with broadly ovate leaves and slender drooping spikes of crimson flowers; southeastern Asia and Australia; naturalized in North America
  15. Pernis apivorus Old World hawk that feeds on bee larvae and small rodents and reptiles
  16. principled based on or demonstrating morality or rightness
  17. Prunus demissa chokecherry of western United States
  18. principalship the post of principal
  19. Prunus dulcis small bushy deciduous tree native to Asia and North Africa having pretty pink blossoms and highly prized edible nuts enclosed in a hard green hull; cultivated in southern Australia and California
  20. principal sum capital as contrasted with the income derived from it

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