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definitions

zone time

noun
  1. standard time as applied at sea, reckoned according to the system of time zones.

Origin of zone time

First recorded in 1905–10
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for zonetime

zonetime

noun
  1. the standard time of the time zone in which a ship is located at sea, each zone extending 7 1/2 ° to each side of a meridian
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012