Origin of ylemMiddle English ; from Middle French ilem ; from uncertain or unknown; perhaps Medieval Latin hylem, accusative of hyle, matter, origin, originally , wood ; from Classical Greek hyl?
Origin of ylemMiddle English, universal matter, from Old French ilem, from Medieval Latin h&ymacron;lem, accusative of h&ymacron;l&emacron;, matter, from Greek h&umacron;l&emacron;.
- (physics, astronomy, cosmology, now chiefly historical) In the Big Bang theory, the hot and dense plasma of which the cosmos consisted at the time of recombination in an early stage of its expansion and cooling, when the first atoms formed and photons decoupled, the source of the cosmic background radiation.
- The word ylem reappeared in popular books on science, following the discovery (in 1964-5) of the predicted (in 1948) cosmic background radiation and publication of its images composed from measurements by satellites (COBE in 1992 and WMAP in 2003).
Resuscitation of Middle English ylem, one of several variants for the Medieval Latin hyle (“matter"), a transliteration of Aristotle's concept of “(fundamental) matter", in Ancient Greek á½•Î»Î· (hulÄ“, “wood(s), material(s), matter, subject") or Ï€ÏÏŽÏ„Î· á½•Î»Î· (“fundamental matter").
First known to have been used in modern English by George Gamow in a paper coauthored with Alpher and Bethe titled "The Origin of Chemical Elements", published in Physical Review, April 1st, 1948.
Note: Claimed to have been found by Robert Herman in a large dictionary. In an interview Gamow also associated ylem with a Hebrew word, which should have been ×™×œ× (substantive “blind"), similar in pronunciation and appropriate for the hypothetical darkness of ylem.