Unresponsive to photoperiods, or changes in photoperiod, that normally elicit physiological or behavioural changes; characterized by such unresponsiveness.
Origin
1950s. From photo- + refractory.
Definition of photorefractory in US English:
photorefractory
adjectiveˌfəʊtə(ʊ)rɪˈfrakt(ə)ri
Ecology Zoology
Unresponsive to photoperiods, or changes in photoperiod, that normally elicit physiological or behavioural changes; characterized by such unresponsiveness.