Quaternary

  1. Proper noun.  (geology) The geological period of the Cenozoic Era immediately following the Tertiary. It is subdivided into the Pleistocene and the Holocene Epochs.
  2. Adjective.  Of fourth rank or order.
  3. Adjective.  Of a mathematical expression containing e.g. x4.

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This entry was last updated on RefTopia from its source on 3/20/2012.