地ち質しつ年ねん代だい

noun

geological time; geologic age

Technical term used in geology and earth sciences to refer to the vast timescale of Earth's history, divided into eons, eras, periods, etc.

• 地ち質しつ年ねん代だいで見みると、人じん類るいの歴れき史しはほんの一いっ瞬しゅんに過すぎない。

  In geological time, human history is just a brief moment.