zbbhttp://www.oed.com/dictionary/zbb_n%3Ftab%3Dmeaning_and_useZBB, n.
First published 1986; not fully revised

ZBBnoun

U.S.
  1. 1976–
    Zero-base(d) budgeting.
    1. 1976
      Z.B.B., as it is widely known, calls for the justification of all spending in relation to priorities.
      New York Times 27 August d 1
    2. 1978
      ZBB was formally delineated and put into practice for the first time by Texas Instruments, Inc., 15 years ago.
      National Civic Review vol. LXVII. 132

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

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