pho·to·re·ac·tion 
(fō′tō-rē-ăkshən)
(fō′tō-rē-ăkshən)n.
A photochemical reaction.
- authoritarianism
- authoritative
- authoritatively
- authoritativeness
- authority
- authorization
- authorize
- Authorized Version
- authorizer
- authorship
- autism
- autism spectrum
- autism spectrum disorder
- autist
- autistic
- autistically
- autistic savant
- auto
- auto-
- autoantibody
- autoantigen
- autobahn
- autobiographer
- autobiographic
- autobiographical