dem·on·stra·tor 
(dĕmən-strā′tər)
(dĕmən-strā′tər)n.
1. One that demonstrates, such as a participant in a public display of opinion.
2. An article or product used in a demonstration.
- photochromatic
- photochromism
- photocoagulate
- photocoagulation
- photocompose
- photocomposition
- photoconduction
- photoconductive
- photoconductivity
- photocopier
- photocopy
- photocurrent
- photodecomposition
- photodegradable
- photodiode
- photodisintegration
- photoduplicate
- photoduplication
- photodynamic
- photodynamically
- photodynamics
- photodynamic therapy
- photoelectric
- photoelectrical
- photoelectrically