safe·light
(sāf′līt′)n. A lamp having one or more color filters allowing moderate darkroom illumination without affecting photosensitive film or paper.
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
safelight
(ˈseɪfˌlaɪt) n (Photography) photog a light that can be used in a room in which photographic material is handled, transmitting only those colours to which a particular type of film, plate, or paper is relatively insensitive
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014
safe•light
(ˈseɪfˌlaɪt)
n. a darkroom light with a filter that transmits only those rays of the spectrum to which films, printing paper, etc., are not sensitive.
[1900–05]
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