- 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
- 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