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period

30 ENTRIES FOUND:
  1. period (noun)
  2. Baroque period
  3. Cambrian Period
  4. Carboniferous Period
  5. Cretaceous Period
  6. Devonian Period
  7. Genroku period
  8. Heian period
  9. Heisei period
  10. Jurassic Period
  11. Kamakura period
  12. Meiji period
  13. Mesolithic Period
  14. Muromachi period
  15. Nara period
  16. Neolithic Period
  17. Ordovician Period
  18. Paleolithic Period
  19. Permian Period
  20. Quaternary Period
  21. Showa period
  22. sidereal period
  23. Silurian Period
  24. Spring and Autumn period
  25. synodic period
  26. Taisho period
  27. Tertiary Period
  28. Tokugawa period
  29. Triassic Period
  30. Warring States period

period

In geology, the basic unit of the geologic time scale. During these spans of time, specific systems of rocks were formed. Originally, the method for defining the sequence of periods was relative; it was based on stratigraphy and paleontology. Carbon-14 dating and similar methods are now used to determine absolute ages for various periods.

This entry comes from Encyclopædia Britannica Concise.
For the full entry on period, visit Britannica.com.

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