Precambrianadj.n.
/priːˈkambrɪən/, U.S. /priˈkæmbriən/ Geology.
A. adj.
Of, relating to, or designating the earliest division of geological time, from the formation of the earth, believed to have been about 4,600 million years ago, to the beginning of the Cambrian period and the Phanerozoic eon, about 542 million years ago.In formal stratigraphic schemes, the Precambrian is divided into the Archaean, Proterozoic, and (in some schemes) Priscoan eons. Very few Precambrian rocks contain fossils, the earliest living organisms with hard parts appearing only towards the end of Precambrian time.
ΘΚΠ
the world > the earth > structure of the earth > age or period > [adjective] > pre-Cambrian
Protozoic1838
prozoic1845
Precambrian1864
Cryptozoic1911
1864 J. W. Salter in Geol. Mag. 1 290 The author suggests that the syenitic trap of St. David's is a part of the old pre-Cambrian land.
1875 J. Croll Climate & Time xx. 343 The length of time embraced by the pre-Cambrian ages of geological history.
1927 W. H. Waggaman Phosphoric Acid, Phosphates, & Phosphatic Fertilizers iii. 99 The most productive area is in S. Australia, where the phosphate occurs associated with Cambrian and pre-Cambrian lime stones [sic].
1951 W. H. Auden Nones (1952) 71 That the red pre-Cambrian light Is gone like Imperial Rome Or myself at seventeen.
1969 E. W. Morse Fur Trade Canoe Routes ii. v. 57 At the upper end of Lac des Alumettes the voyageurs came..into close contact with the granite of the Precambrian Shield, rising straight from the water.
1998 S. C. Morris Crucible of Creation vi. 162 There is certainly evidence that in the late Precambrian times many of the present-day continents were welded together into..a super-continent.
2001 J. Waterman Arctic Crossing ii. 143 Seen by the high-flying sandhill cranes, the Horton River curls southeastward up out of the giant bay, gouging out Precambrian granitic canyons.
B. n.
With the. The Precambrian division of geological time; the system of rocks dating from this.
ΘΚΠ
the world > the earth > structure of the earth > age or period > [noun] > Pre-Cambrian
Precambrian1915
Cryptozoic1922
1910 P. Lake & R. H. Rastall Text-bk. Geol. xvii. 292 Everywhere in the British Isles there is a marked unconformity between the pre-Cambrian and the later deposits.]
1915 C. Schuchert Text-bk. Geol. II. xxvii. 540 The result..serves to make prominent the two most significant and distinctive features of the pre-Cambrian: (1) the wide-spread crustal revolutions,..and (2) the profound depth to which erosion has planed.
1971 Nature 25 June 498/1 The Pre-Cambrian covers 85% of the total length of geological time and is the longest geological division.
1992 Economist 10 Oct. 123/1 The defining feature of the Precambrian..is its lack of useful fossils.
This entry has been updated (OED Third Edition, March 2007; most recently modified version published online March 2022).
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adj.n.1864