zinc-platedhttp://www.oed.com/dictionary/zinc-plated_adj%3Ftab%3Dmeaning_and_usezinc-plated, adj.
First published 1921; not fully revised

zinc-platedadjective

  1. 1859–
    1. 1859
      There is the rotunda of the Bank of England, with its many-slamming, zinc-plated doors.
      G. A. Sala, Twice round Clock 117
    2. 1966
      Zinc-plated coatings are usually purer than hot-dipped coatings.
      McGraw-Hill Encyclopedia of Science & Technology (revised edition) vol. IV. 531/1

Originally published as part of the entry for zinc, n.

zinc, n. was first published in 1921; not fully revised.