工学 食品安全 释 food safety objective；FSO 食品安全目标 食品中的某种危害可提供或促进适当保护水平（appropriate level of protection，ALOP）的最大允许频率或浓度。食品安全目标的概念仅限于食品安全，不涉及质量。
网络与数据通信 无线网络 释文 free space optics, FSO 自由空间光束
- opposed anvils
- opposing reaction
- opposite
- opposite algebra
- opposite and complementary
- opposite and equal
- opposite angles
- opposite category
- opposite composition law
- opposite derivative
- opposite dihedral angle
- opposite direction
- opposite direction ray
- opposite edges
- opposite event
- opposite face
- opposite form
- opposite graduation
- opposite group
- opposite half-spaces
- opposite leaf
- oppositely directed
- oppositely directed traveling wave 9 ODTW
- opposite number
- opposite orientation