photoperiod

noun
pho·​to·​pe·​ri·​od | \ ˌfō-tō-ˈpir-ē-əd How to pronounce photoperiod (audio) \

Definition of photoperiod

: a recurring cycle of light and dark periods of constant length also : photophase sense 2

Other Words from photoperiod

photoperiodic \ ˌfō-​tō-​ˌpir-​ē-​ˈä-​dik How to pronounce photoperiod (audio) \ adjective
photoperiodically \ ˌfō-​tō-​ˌpir-​ē-​ˈä-​di-​k(ə-​)lē How to pronounce photoperiod (audio) \ adverb

Examples of photoperiod in a Sentence

Recent Examples on the Web As mentioned earlier, brood fish are housed in the same indoor tanks where scientists fool them into spawning by playing around with photoperiods and water temperature. Matt Williams, Dallas News, 9 May 2020 The prompt to begin growing a fresh set of antlers is regulated by a rise in testosterone, which is triggered by photoperiod. Andrew Mckean, Outdoor Life, 26 Mar. 2020 About 10 varieties are being grown using photoperiod manipulation, which will be featured on the tours. Lauren Delgado, OrlandoSentinel.com, 9 July 2018 About 10 varieties are being grown using photoperiod manipulation, which will be featured on the tours. Lauren Delgado, OrlandoSentinel.com, 9 July 2018 About 10 varieties are being grown using photoperiod manipulation, which will be featured on the tours. Lauren Delgado, OrlandoSentinel.com, 9 July 2018 About 10 varieties are being grown using photoperiod manipulation, which will be featured on the tours. Lauren Delgado, OrlandoSentinel.com, 9 July 2018 About 10 varieties are being grown using photoperiod manipulation, which will be featured on the tours. Lauren Delgado, OrlandoSentinel.com, 9 July 2018 About 10 varieties are being grown using photoperiod manipulation, which will be featured on the tours. Lauren Delgado, OrlandoSentinel.com, 9 July 2018 See More

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'photoperiod.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

First Known Use of photoperiod

1920, in the meaning defined above

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Time Traveler for photoperiod

Time Traveler

The first known use of photoperiod was in 1920

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Dictionary Entries Near photoperiod

photopathy

photoperiod

photoperiodism

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Statistics for photoperiod

Cite this Entry

“Photoperiod.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/photoperiod. Accessed 25 May. 2022.

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More Definitions for photoperiod

photoperiod

noun
pho·​to·​pe·​ri·​od | \ ˌfōt-ō-ˈpir-ē-əd How to pronounce photoperiod (audio) \

Medical Definition of photoperiod

: a recurring cycle of light and dark periods of constant length

Other Words from photoperiod

photoperiodic \ -​ˌpir-​ē-​ˈäd-​ik How to pronounce photoperiod (audio) \ adjective
photoperiodically \ -​i-​k(ə-​)lē How to pronounce photoperiod (audio) \ adverb

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