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chicken-and-egg

[chik-uh n-uh n-eg, -uh nd-]
adjective
  1. of, relating to, or being a dilemma of which of two things came first or of which is the cause and which the effect: a chicken-and-egg question of whether matter or energy is the basis of the universe.
Also chick·en-or-egg [chik-uh n-er-eg] /ˈtʃɪk ən ərˈɛg/.

Origin of chicken-and-egg

First recorded in 1955–60
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018

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