film - flan
- fired flux
- fired magnesite
- fired magnesite brick
- firepot
- firing
- firing cycle
- firing machine
- firing range
- firing rate
- firing shrinkage
- firm-and-impervious joint
- first blow
- first coat
- first cut and finish scrap delay
- first draw
- first feed ore addition
- first finishing
- first harmonic
- first helper
- first layer
- first long row elements
- first matte
- first nearest neighbour
- first operating period
- first pass
- first pickling
- first reduction
- first shape
- first slag
- first stage of annealing
- first stage of graphitization
- first-class welding
- first-draft drawing
- first-order diffracted beam
- first-order lag
- first-run slag
- first-stage graphitization
- fiscal year
- fish eye
- fish scale