Of or relating to a cosmological theory proposing that the known universe originated in the collision of two other three-dimensional universes traveling in a hidden fourth dimension. This scenario does not require a singularity at the moment of the Big Bang.
[Greek ekpurōsis, conflagration, cyclically recurring conflagration in which the universe is destroyed and reborn according to Stoic philosophy (from ex, ek, out of; see eghs in the Appendix of Indo-European roots + pūr, pur-, fire; see paəw in the Appendix of Indo-European roots + -ōsis, n. suff.) + -OTIC.]
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Indo-European & Semitic Roots Appendices
Thousands of entries in the dictionary include etymologies that trace their origins back to reconstructed proto-languages. You can obtain more information about these forms in our online appendices:
The Indo-European appendix covers nearly half of the Indo-European roots that have left their mark on English words. A more complete treatment of Indo-European roots and the English words derived from them is available in our Dictionary of Indo-European Roots.