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.
a group of four.
the number four.
(initial capital letter)Geology. the Quaternary Period or System.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2024
How to use quaternary in a sentence
El Centro Regional is not a tertiary or quaternary care center, meaning it’s not a hospital with extensive specialty service or care.‘Like drowning in slow motion’: Life on the ground at one of America’s hardest-hit COVID-19 hospitals | matthewheimer | December 1, 2020 | Fortune
And the bones of man himself appear, extending through what is known as the quaternary or Pleistocene period.Man And His Ancestor | Charles Morris
Subspeciation has been enhanced by the late quaternary mountain building which was prevalent over the western United States.Speciation in the Kangaroo Rat, Dipodomys ordii | Henry W. Setzer
A distinct species characterised the quaternary deposits of South America.Mythical Monsters | Charles Gould
The Tertiary and quaternary formations are partly of marine and partly of terrestrial and fresh-water origin.Geology | James Geikie
The Post-tertiary or quaternary division comprises the concluding chapters of geological history.Geology | James Geikie
British Dictionary definitions for quaternary (1 of 2)
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
the number four or a set of four
British Dictionary definitions for Quaternary (2 of 2)
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
Scientific definitions for quaternary
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.
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 © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.