photoperiod

noun pho·to·pe·ri·od \ ˌfō-tō-ˈpir-ē-əd \

Definition of photoperiod

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

photoperiodic

play \ˌfō-tō-ˌpir-ē-ˈä-dik\ adjective

photoperiodically

play \ˌfō-tō-ˌpir-ē-ˈä-di-k(ə-)lē\ adverb

First Known Use of photoperiod

1920


Medical Dictionary

photoperiod

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

medical Definition of photoperiod

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

photoperiodic

play \-ˌpir-ē-ˈäd-ik\ adjective

photoperiodically

play \-i-k(ə-)lē\ adverb

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