designating or of the division of geologic time covering all the time before the Cambrian Period, equivalent to the Archean Eon and the Proterozoic Eon
the Precambrian time or its rocks
Of, relating to, or being the geologic time period between Hadean Time and the Cambrian Period, often subdivided into the Archean and Proterozoic Eras, comprising most of the earth's history and marked by the appearance of primitive forms of life. See Table at geologic time.
The Precambrian Eon.