European Commission 
A group, appointed by agreement among the governments of the European Union, which initiates Union action and safeguards its treaties. It meets in Brussels.
- photoorganotroph
- photoorganotrophic
- photoorganotrophy
- photo-oxidation
- photo-oxidative
- photo-oxidise
- photo-oxidizable
- photo-oxidize
- photo-pass
- photopathy
- photopeak
- photoperiod
- photoperiodic
- photoperiodically
- photoperiodism
- photopheresis
- photophil
- photophile
- photophilic
- photophilous
- photophily
- photophob
- photophobe
- photophobia
- photophobic