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[kwot-er-ner-ee, kwuh-tur-nuh-ree] /ˈkwɒt ərˌnɛr i, kwəˈtɜr nə ri/
consisting of four.
arranged in fours.
(initial capital letter) Geology. noting or pertaining to the present period of earth history, forming the latter part of the Cenozoic Era, originating about 2 million years ago and including the Recent and Pleistocene Epochs.
Metallurgy. (of an alloy) having four principal constituents.
noun, plural quaternaries.
a group of four.
the number four.
(initial capital letter) Geology. the Quaternary Period or System.
Origin of quaternary
late Middle English
1400-50; late Middle English < Latin quaternārius consisting of four, equivalent to quatern(ī) four at a time + -ārius -ary Unabridged
Based on the Random House Dictionary, © Random House, Inc. 2018.
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Examples from the Web for quaternary
Historical Examples
  • “Quartenary” was amended to “quaternary” in the first paragraph.

  • They are referred to the dawn of the quaternary or Pleistocene period.

    Prehistoric Man W. L. H. Duckworth
  • In Europe it has appeared since the neolithic age, after the quaternary period.

    The Races of Man Joseph Deniker
  • How does this affect the most characteristic of all quaternary forms, that of man?

    Human Origins Samuel Laing
  • Does pre-glacial mean Pliocene, or is it included in the quaternary?

    Human Origins Samuel Laing
  • It may have been in the Tertiary, the quaternary, or not until the Recent period.

    Human Origins Samuel Laing
  • Lastly, only in the quaternary comes the genus Equus, or true horse.

    Evolution Joseph Le Conte
  • Ternary, and quaternary, consist of three and four elements.

    Elements of Chemistry, Antoine Lavoisier
  • The flora itself at the quaternary age was of extreme vigor.

  • Normal gray is black and white mixed, but quaternary colors are also called grays, or colors of the dull or neutral scale.

    Color Value C. R. Clifford
British Dictionary definitions for quaternary


consisting of fours or by fours
fourth in a series
(chem) containing or being an atom bound to four other atoms or groups: a quaternary ammonium compound
(maths) having four variables
noun (pl) -naries
the number four or a set of four
Word Origin
C15: from Latin quaternārius each containing four, from quaternī by fours, distributive of quattuor four


of, denoting, or formed in the most recent period of geological time, which succeeded the Tertiary period nearly two million years ago
the Quaternary, the Quaternary period or rock system, divided into Pleistocene and Holocene (Recent) epochs or series
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition
© William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins
Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
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Word Origin and History for quaternary

early 15c., "consisting of four parts," from Latin quaternarius "of four each, containing four," from quaterni "four each, by fours," from quater "four times," related to quattuor "four" (see four). Also as a noun, "the number four" (mid-15c.), from Latin quaternarius.

In geological sense, attested from 1843 in English, proposed 1829 by French geologist Jules Pierre François Stanislas Desnoyers (1800-1887) as name for "the fourth great epoch of geological time," but because it comprises only the age of man, and the other epochs are many hundred times longer, not all accepted it.

Online Etymology Dictionary, © 2010 Douglas Harper
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quaternary in Medicine

quaternary qua·ter·nar·y (kwŏt'ər-něr'ē, kwə-tûr'nə-rē)

  1. Consisting of four; in fours.

  2. Relating to an atom bonded to four carbon atoms.

The member of a group or series that is fourth in order.
The American Heritage® Stedman's Medical Dictionary
Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.
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quaternary in Science
Noun  Quaternary. The second and last period of the Cenozoic Era, from about 2 million years ago to the present. During this time the continents were situated approximately as they are today, although the geography was different due to fluctuations in sea levels caused by the advance and retreat of ice sheets. Humans first appeared during this period. See Chart at geologic time.

Adjective  Relating to or having a carbon atom that is attached to four other carbon atoms in a molecule. Quaternary pentane, for example, contains five carbon atoms of which one is in the center and the other four are each attached to it.
The American Heritage® Science Dictionary
Copyright © 2002. Published by Houghton Mifflin. All rights reserved.
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