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nidation

American  
[nahy-dey-shuhn] / naɪˈdeɪ ʃən /

noun

Embryology.
  1. implantation of an embryo in the lining of the uterus.


nidation British  
/ naɪˈdeɪʃən /

noun

  1. physiol another name for implantation

"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 nidation

1870–75 for an earlier sense; nid(us) + -ation