quaternary(redirected from the Quaternary)
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1. Chem containing or being an atom bound to four other atoms or groups
2. Maths having four variables
1. of, denoting, or formed in the most recent period of geological time, which succeeded the Tertiary period nearly two million years ago
2. the. the Quaternary period or rock system, divided into Pleistocene and Holocene (Recent) epochs or series
The second period of the Cenozoic geologic era, following the Tertiary, and including the last 2-3 million years.