kvartäärisen

Kvartäärisen is a Swedish adjective meaning "quaternary". It is most commonly used in geological contexts to refer to the Quaternary period, the most recent geological period of the Cenozoic Era. This period spans from approximately 2.58 million years ago to the present day. The Quaternary period is characterized by repeated glacial cycles and significant changes in Earth's climate, leading to the formation of ice sheets and extensive sea-level fluctuations. It is also the period during which modern humans evolved and spread across the globe.

In a broader sense, "kvartäärisen" can also refer to anything belonging to the fourth order or level. This could be applied in various fields, such as chemistry where it might describe a quaternary carbon atom (a carbon atom bonded to four other carbon atoms), or in mathematics where it could denote a fourth-degree polynomial. However, its primary and most widespread usage remains within geology, denoting phenomena related to the Quaternary period. The term itself derives from the Latin word "quaternarius," meaning "consisting of four."