I. |fōd.(ˌ)ō+ noun
Etymology: phot- + period
: the relative lengths of alternating periods of lightness and darkness as they affect the growth and maturity of an organism (as in the effect upon the flowering of plants and the breeding of animals) — compare thermoperiod
• pho·to·periodic or pho·to·periodical “+ adjective
• pho·to·periodically “+ adverb
II. noun
: photophase 2 herein