[ad_1] adjective, noun Geology.
- noting or pertaining to the earlier half of the Precambrian Era, from about 5 billion to 2.5 billion years ago, during which the earliest datable rocks were formed and from which the oldest known fossil forms, blue-green algae and bacteria, have been recovered.
- the Archeozoic division of geologic time or the rock systems formed then.
- a former word for
- a variant spelling (esp US) of
- Another spelling of Archeozoic.
- See Archean.