- A faint white or yellowish arc-shaped light, similar to a rainbow, that sometimes appears in fog opposite the sun. Also called seadog 雾虹：有时在雾中逆光处出现的与彩虹相似的弧状模糊的白色或微黄的光 也作 seadog
- Forrestal
- fors
- forsake
- forsaken
- forsakes
- forsaking
- forsook
- forsooth
- forspent
- Forssmann
- Forster
- forswear
- forswearing
- forswears
- forswore
- forsworn
- forsythia
- forsythias
- Forsyth School for Dental Hygienists
- Forsyth School for Dental Hygienists
- Forsyth Technical Community College
- fort
- fort
- fort.
- Fortaleza