Definition of "primordial"

primordial

/pɹaɪˈmɔː.di.əl/

adjective
not comparable
1. first, earliest or original
  Quotations
  the primordial facts of our intelligent nature
  1859–1860, William Hamilton, edited by H[enry] L[ongueville] Mansel and John Veitch, Lectures on Metaphysics and Logic […], volumes (please specify |volume=I to IV), Edinburgh, London: William Blackwood and Sons
  As an archetypal image of primordial unity, the cosmic egg suggests that there is unity and fragmentation, eternity and time.
  1981, William Irwin Thompson, The Time Falling Bodies Take to Light:Mythology, Sexuality and the Origins of Culture, page 9
2. (biology) characteristic of the earliest stage of the development of an organism, or relating to a primordium
3. primeval
4. Of an element or isotope: occurring primordially (on Earth) (i.e. inherited from when the Earth was formed); because it is stable, or radioactive but so long-lived that some is left over from when the Earth was formed. For example, primordial radioisotopes (T = half-life) include uranium-235 (T = 7×108 years), potassium-40 (T = 1.25×109 years), uranium-238 (T = 4.5×109 years), and thorium-235 (T = 1.4×1010 years).
noun
plural primordials
1. A first principle or element.