quaternary has definitions from the fields of mathematics,geology
1
[ noun ] (geology) last 2 million years
2
[ adjective ] (geology) coming next after the third and just before the fifth in position or time or degree or magnitude

Synonyms

fourth 4th

Examples

"the quaternary period of geologic time extends from the end of the tertiary period to the present"

Related terms

ordinal

3
[ adjective ] consisting of or especially arranged in sets of four

Synonyms

quaternate

Examples

"quaternate leaves" "a quaternary compound"

Related terms

multiple

4
[ noun ] (mathematics) the cardinal number that is the sum of three and one

Related terms

digit

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