a combining form meaning “light” (photobiology); also used to represent “photographic” or “photograph” in the formation of compound words: photocopy.
Words nearby photo-
Also especially before a vowel, phot-.
Origin of photo-
< Greek, combining form of phôs (genitive phōtós)
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British Dictionary definitions for photo-
of, relating to, or produced by lightphotosynthesis
indicating a photographic processphotolithography
Word Origin for photo-
from Greek phōs, phōt- light
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
Medical definitions for photo-
Light; radiant energy:photosynthesis.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.
Scientific definitions for photo-
A prefix that means light, as in photoreceptor.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.