- falcate
- family
- fanfin
- fang
- FAO
- fauna
- fecundity
- female
- fen
- feral
- ferruginous
- fertility
- fertilization
- ficiform
- filaments
- fin
- finray
- fish
- fissure
- fjord
- flabellate
- flagellum
- flap
- flatfish
- flexure
- floodland
- flora
- FNAM
- foliaceous
- foothill
- foramen
- foramina
- foregut
- forehead
- forked fin
- forma
- formalin
- fossa
- fouling
- foveola
- freshwater
- friable
- frill
- fringed
- frontal
- Frontoparietal
- fulcral
- fulvous
- fungi
- furcate
- furrow
- fusiform