hemera

noun

hem·​era

ˈhemərə

plural hemerae

-ə(ˌ)rē

also hemera

1

: a stratigraphic zone comprising the time range of a particular fossil species

2

: a period of time during which a race of organisms is at the apex of its evolution

Word History

Etymology

New Latin, from Greek hēmera day; akin to Greek ēmar day, Armenian aur

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