zygodonthttp://www.oed.com/dictionary/zygodont_adj%3Ftab%3Dmeaning_and_usezygodont, adj.
First published 1921; not fully revised

zygodontadjective

  1. 1888–
    Having molar teeth with an even number of cusps arranged in pairs; having cusps thus arranged, as a molar tooth.
    1. 1888
      The zygodont (quadritubercular) type.
      American Naturalist vol. 22 832

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

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