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Glite Dictionary
ylem

ylem

1 9.9
A hot, dense substance in the early universe that became all matter
  • noun
  • /ˈiːlɛm/
  • Archaic
: ylem
  • The concept of ylem helps researchers understand the conditions present during the universe's earliest moments.

Examples

  • Scientists believe that ylem played a crucial role in the formation of stars and galaxies in the early universe.

  • This slide, presented during a lecture on nucleosynthesis, depicts Gamow materializing out of a bottle of "Ylem"—the primordial substance from which the elements supposedly formed.

    Academic text (1994)

  • Gamow brought to Ann Arbor a slide of the dictionary definition of the obsolete word "ylem," which he had adopted for the primordial matter of the Big Bang.

    Academic text (1994)

  • Robert Herman, George Gamow, and Ralph Alpher (left to right) with their bottle of YLEM, a fanciful primordial form of matter they concocted.

    Academic text (2003)

  • In cosmology, ylem is considered the primordial substance from which all matter originated after the Big Bang.

Surface Forms

ylem singular
ylems plural

Etymology

Ylem was an old word for basic 'matter' that was revived by scientists in the 20th century to name the hot, first 'stuff' of the Big Bang. A helpful way to remember it is to think of ylem like element, the very first 'element' or building 'stuff' of the universe.