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Pronunciation: ze'ro


  1. The figure 0, indicating the absence of magnitude, or nothing.
  2. In thermometry, the point from which the figures on the scale start in one or the other direction; in the Celsius and Réaumur scales, zero indicates the freezing point for distilled water; in the Fahrenheit scale, it is 32° below the freezing point of water.

[Sp. fr. Ar. sifr, cipher]

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© Copyright 2018 Wolters Kluwer. All Rights Reserved. Review date: Sep 19, 2016.