zygostylehttp://www.oed.com/dictionary/zygostyle_n%3Ftab%3Dmeaning_and_usezygostyle, n.
First published 1921; not fully revised

zygostylenoun

  1. 1881–
    (See quot.).
    1. 1881
      The caudal vertebræ are few and end in a bone, shaped somewhat lika a plough~share, called the zygostyle.
      St. G. Mivart, Cat 463

Originally published as part of the entry for zygo-, comb. form

zygo-, comb. form was first published in 1921; not fully revised.