photoperiod

noun pho·to·pe·ri·od \-ˈpir-ē-əd\

Definition of PHOTOPERIOD

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

— pho·to·pe·ri·od·ic \-ˌpir-ē-ˈä-dik\ adjective

— pho·to·pe·ri·od·i·cal·ly \-di-k(ə-)lē\ adverb

See photoperiod defined for kids

1920

Medical Dictionary

noun pho·to·pe·ri·od \ˌfōt-ō-ˈpir-ē-əd\

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

—pho·to·pe·ri·od·ic \-ˌpir-ē-ˈäd-ik\ adjective

—pho·to·pe·ri·od·i·cal·ly \-i-k(ə-)lē\ adverb

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