Definition of quaternary
1a : of, relating to, or consisting of four units or membersb : of, relating to, or being a number system with a base of four
2 capitalized : of, relating to, or being the geological period from the end of the Tertiary to the present time or the corresponding system of rocks — see geologic time table
3 : consisting of, containing, or being an atom bonded to four other atoms
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Origin and Etymology of quaternary
Latin quaternarius, from quaterni four each
First Known Use: 1605
Other Geology Terms
anthracite, boulder, cwm, erratic, igneous, intrusive, mesa, sedimentary, silt, swale
quaternary
Definition of quaternary
quaternaries
1 capitalized : the Quaternary period or system of rocks
2 : a member of a group fourth in order or rank
1880
First Known Use of quaternary
1880
Other Geology Terms
anthracite, boulder, cwm, erratic, igneous, intrusive, mesa, sedimentary, silt, swale
Medical Dictionary
quaternary
Medical Definition of quaternary
quaternaries
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