- A watch that can be instantly started and stopped by pushing a button and used to measure an exact duration of time.跑表，记秒表：用于准确测量一段持续时间的可由按钮随时开关的表
- photoconductivity
- photocopier
- photocopier
- photocopy
- photocurrent
- photodecomposition
- photodegradable
- photodisintegration
- photodrama
- photoduplicate
- photodynamic
- photodynamics
- photoed
- photoelectric
- photoelectric cell
- photoelectric effect
- photoelectron
- photoemission
- photoengrave
- photoengraving
- photo-essay
- photo finish
- photofinishing
- photoflash
- photoflash bulb