con·stan·cy 
(kŏnstən-sē)
(kŏnstən-sē)n.
1. Steadfastness, as in purpose or affection; faithfulness.
2. The condition or quality of being constant; changelessness.
- photodynamic
- photodynamically
- photodynamics
- photodynamic therapy
- photoelectric
- photoelectrical
- photoelectrically
- photoelectric cell
- photoelectric effect
- photoelectron
- photoemission
- photoemission spectroscopy
- photoengrave
- photoengraver
- photoengraving
- photo-essay
- photo essay
- photo-essayist
- photo finish
- photoflash
- photoflood
- photofluorogram
- photofluorographic
- photofluorography
- photog