- free ultrafilter
- free union
- free universal algebra
- free unknown
- free variable
- free vector
- free vertex
- free walk
- freezing of coefficients
- Frege, F.L.G.
- Frege syllogism
- Freiheitssatz 【德文】
- French curve
- French empiricism
- Frenet formula
- Frenet frame
- Frenet, J.F.
- Frenet-Serret formula
- Frenet trihedron
- Frenicle de Bessy, B.
- frequency
- frequency approach
- frequency bandwidth constraint
- frequency capture
- frequency characteristic