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ex nihilo

[eks nahy-uh-loh, nee-uh-]
adverb, adjective Latin.
  1. out of nothing; from nothing.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
Word Origin and History for ex nihilo

Latin, literally "out of nothing," from ex "out of" (see ex-) + nihilo, ablative of nihil "nothing" (see nil).

Online Etymology Dictionary, © 2010 Douglas Harper