Quaternary

From Latin quaternārius (“consisting of four”), from quaternī (“by fours”); in numerical sense via Middle English quaternary. Compare French quaternaire.

• enPR: kwŏt′ər-nĕr′ē, kwə-tûr′nə-rē
• (General American) IPA^(key): /ˈkwɑt.əɹˌnɛɹ.i/, /kwəˈtɜɹ.nə.ɹi/
• (Received Pronunciation) IPA^(key): (rare) /ˈkwɒt.əˌnɛɹ.iː/, /kwəˈtɜː.nə.ɹiː/

Quaternary

1. (geology) The geological period of the Cenozoic Era immediately following the Tertiary. It is subdivided into the Pleistocene and the Holocene Epochs.

   Synonym: Age of Man (dated)

   Meronyms: Pleistocene, Holocene, Anthropocene, assholocene

2. Alternative letter-case form of quaternary.

• Neogene
• Tertiary

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• William Dwight Whitney, Benjamin E[li] Smith, editors (1911), “Quaternary”, in The Century Dictionary […], New York, N.Y.: The Century Co., →OCLC, page 4901, column 2.
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• “Quaternary”, in Webster’s Revised Unabridged Dictionary, Springfield, Mass.: G. & C. Merriam, 1913, →OCLC.
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• “Quaternary”, in Cambridge English Dictionary, Cambridge, Cambridgeshire: Cambridge University Press, 1999–present.
• “Quaternary”, in Collins English Dictionary.
• “Quaternary”, in Dictionary.com Unabridged, Dictionary.com, LLC, 1995–present.
• “Quaternary”, in OneLook Dictionary Search.