Found 2 items, similar to archaean.
English → English (WordNet)
Definition: archaean
archaean
adj : used of the earliest known rocks [syn:
archean]
English → English (gcide)
Definition: Archaean
Archaean
\Ar*ch[ae]"an\, a. [Gr. 'archai^os ancient, fr. 'archh`
beginning.]
Ancient; pertaining to the earliest period in geological
history.
[1913 Webster]
Archaean
\Ar*ch[ae]"an\, n. (Geol.)
The earliest period in geological period, extending up to the
Lower Silurian. It includes an Azoic age, previous to the
appearance of life, and an Eozoic age, including the earliest
forms of life.
[1913 Webster]
Note: This is equivalent to the formerly accepted term Azoic,
and to the Eozoic of Dawson.
[1913 Webster]