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zygo-

American  
especially before a vowel, zyg-.
  1. a combining form meaning “yoke,” “yoked,” “yoke-shaped,” used in the formation of compound words.

    zygomorphic.


zygo- British  

combining form

  1. indicating a pair or a union

    zygodactyl

    zygospore

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Etymology

Origin of zygo-

Combining form of Greek zygón yoke 1