zero-base definition by Webster's New World
Webster's New World College Dictionary Copyright © 2010 by Wiley Publishing, Inc., Cleveland, Ohio. Used by arrangement with John Wiley & Sons, Inc.
designating or of a technique for preparing a budget, in which each proposed item is evaluated on its merits without considering any previous budget
Origin: from the idea of starting at zero
zero-base definition by American Heritage Dictionary
Having each expenditure or item justified as to need or cost: “Zero-base budgeting requires its practitioners to justify every dollar they spend” (Wall Street Journal).