| Term | Definition |
| fraction | one or more of the equal parts of a whole; fragment |
| fractious | apt to break out into a passion; cross; irritable |
| fracture | 1. break or crack 2. breaking of a bone |
| fragile | easily broken; frail; delicate |
| fragment | part broken off |
| infraction | act of breaking; breach; violation, as an infraction of a law |
| refract | bend (literally, "break back") from a straight path (as when light rays, having traveled through air, change direction when entering water, or as when sunlight-- having traveled through a prism-- breaks up into the colors of the rainbow) |
| refractory | resisting; intractable; hard to manage |