thermoperiod

noun

ther·​mo·​period

¦thərmō+

: the period of exposure of a plant to a particular temperature

specifically : the period characteristic of the diurnal alternation of day and night temperature when both period and temperature are at or near the optimum for the induction of various activities (as growth or flowering) compare photoperiod

thermoperiodic

¦thər(ˌ)mō+

adjective

Word History

Etymology

therm- + period

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