zenzizenzizenzichttp://www.oed.com/dictionary/zenzizenzizenzic_n%3Ftab%3Dmeaning_and_usezenzizenzizenzic, n.
First published 2018

† zenzizenzizenzicnoun

Mathematics. rare. Obsolete.
  1. 1557–1690
    The square of a square of a square number; the eighth power of a number.
    1. 1557
      Zenzizenzizenzikes, that is squares of squared squares.
      R. Recorde, Whetstone of Witte sig. Hivv
    2. a1690
      He may be produced 5 wayes, by Multiplying..3. The Cube into the Zenzizenzizenzike.
      S. Jeake, Λογιστικηλογία (1696) 191

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

zenzizenzizenzic, n. was first published in 2018.