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A form of matter hypothesized by proponents of the Big Bang theory to have existed before the formation of the chemical elements.

[Middle English, universal matter, from Old French ilem, from Medieval Latin hȳlem, accusative of hȳlē, matter, from Greek hūlē.]


(Astronomy) the original matter from which the basic elements are said to have been formed following the explosion postulated in the big bang theory of cosmology
[Middle English, from Old French ilem, from Latin hӯlē stuff, matter, from Greek hulē wood, matter]
ThesaurusAntonymsRelated WordsSynonymsLegend:
Noun1.ylem - (cosmology) the original matter that (according to the big bang theory) existed before the formation of the chemical elements
matter - that which has mass and occupies space; "physicists study both the nature of matter and the forces which govern it"
cosmogeny, cosmogony, cosmology - the branch of astrophysics that studies the origin and evolution and structure of the universe
References in periodicals archive ?
Taking part in the local Battle of Grandmasters as the youngest entry in the women's division, she scored one positive result after another and wound up second behind the seasoned Ralf Ylem Jose by half a point.
emerges as a sign of life in Ylem (1972), a musical fable depicting, in a mere twenty-six minutes, the expansion and contraction of our universe and its renewed expansion thereafter in an alternate space-time outside the concert chamber.
In San Francisco, Blue Room Gallery presented "Interfacing Ideas: Fine Art Meets Technology," works by 17 artists of the YLEM Organization, an art-science group whose name comes from big-bang theories.