Main Entry: pho·to·bi·ol·o·gy

Pronunciation: \ˌfō-tō-(ˌ)bī-ˈä-lə-jē\

Function: noun

Etymology: International Scientific Vocabulary

Date: 1935

: a branch of biology that deals with the effects on living organisms of radiant energy (as light)

— pho·to·bi·o·log·i·cal \-ˌbī-ə-ˈlä-ji-kəl\ also pho·to·bi·o·log·ic \-ˈlä-jik\ adjective

— pho·to·bi·ol·o·gist \-(ˌ)bī-ˈä-lə-jist\ noun