陰いん生せい代だい

noun, noun which may take the genitive case particle 'no'

Cryptozoic; Cryptozoic period

Geological term for the early eon before abundant visible life; used in academic or scientific contexts.

• 陰いん生せい代だいは、先せんカンブリア時じ代だいの大だい部ぶ分ぶんを含ふくむ地ち質しつ時じ代だい区く分ぶんである。

  The Cryptozoic is a geological era that includes most of the Precambrian.