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thermoperiodicity

American  
[thur-moh-peer-ee-uh-dis-i-tee] / ˌθɜr moʊˌpɪər i əˈdɪs ɪ ti /
Also thermoperiodism

noun

Biology.
  1. the effect on an organism of rhythmic fluctuations in temperature.


Etymology

Origin of thermoperiodicity

First recorded in 1940–45; thermo- + periodicity