the interval in a 24-hour period during which a plant or animal is exposed to light.
- pho·to·pe·ri·od·ic [foh-tuh-peer-ee-od-ik], /ˌfoʊ təˌpɪər iˈɒd ɪk/, pho·to·pe·ri·od·i·cal, adjective
- pho·to·pe·ri·od·i·cal·ly, adverb
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2023
How to use photoperiod in a sentence
Broad limits to functional reproductive activity seem to be set by the photoperiod—neuroendocrine system.The Breeding Birds of Kansas | Richard F. Johnston
These captives had been kept for several months at a temperature of 21 degrees Centigrade, and on a daily photoperiod of 15 hours.
The mice were kept in a room in which temperature and photoperiod were controlled.
In general, Tb's showed a marked circadian cycle in phase with photoperiod.
British Dictionary definitions for photoperiod
the period of daylight in every 24 hours, esp in relation to its effects on plants and animals: See also photoperiodism
- photoperiodic, adjective
- photoperiodically, adverb
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
Scientific definitions for photoperiod
The duration of an organism's daily exposure to light, considered especially with regard to the phenomena of photoperiodism.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.