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definitions

running light

noun
  1. any of various lights required to be displayed by a vessel or aircraft operating between sunset and sunrise.

Origin of running light

First recorded in 1880–85
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for running light

running light

noun
  1. nautical one of several white, red, or green lights displayed by vessels operating at night
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