zymometerhttp://www.oed.com/dictionary/zymometer_n%3Ftab%3Dmeaning_and_usezymometer, n.
First published 1921; not fully revised

zymometernoun

  1. 1842–
    Stressed as zyˈmometer.
    1. 1842
      Zumometer, or Zumosimeter, an instrument intended to show the degree to which fermentation has proceeded in different fermenting liquors.
      W. T. Brande, Dictionary of Science, Literature & Art 1343/2

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

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