Movies, Television. a light source placed behind an actor, object, or scene to create a highlight that separates the subject from the background.
verb (used with object), back·light·ed or back·lit, back·light·ing.
to illuminate (something) from behind.
Origin of backlight
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
light falling on a photographic or television subject from the rear
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