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chicken-and-egg

American  
[chik-uhn-uhn-eg, -uhnd-] / ˈtʃɪk ən ənˈɛg, -ənd- /
Also chicken-or-egg

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.

Etymology

Origin of chicken-and-egg

First recorded in 1955–60

Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.