Definition of photopositivity in US English:

photopositivity

noun

Zoology
  • Tendency to move towards light.

Origin

1960s; earliest use found in Journal Insect Physiology. From photo- + positivity, after photopositive.

Pronunciation

photopositivity

/ˌfəʊtəʊˌpɒsɪˈtɪvɪti/