fabella: diminutive of Latin faba = a bean, hence, a sesamoid bone found in the lateral head of gastrocnemius.
facet: Latin facies = face, hence a small smooth bony surface, either coated with articular cartilage or the site of a tendinous attachment (cf. a facet on a diamond).
facilitate: Latin facilis = easy, hence, to make easy.
falciform: adjective, Latin falx = a sickle, and forma = form, hence, shaped like a sickle.
falx: Latin = sickle, hence, the sickle-shaped falx cerebri and falx cerebelli, adjective - falciform.
fascia: Latin = band or bandage, hence the fibrous wrapping of muscles - deep fascia, or the subcutaneous layer of fatty connective tissue - superficial fascia, adjective, fascial.
fasciculus: diminutive of Latin fascis = bundle, hence, a bundle of nerve or muscle fibres.
fastigius: Latin fastigium = summit, hence the peak of the 4th ventricle, adjective - fastigial.
flocculus: diminutive of Latin floccus, a tuft. Hence resembling a picture of a little cloud, with a woolly top and a flat base, as in flocculus cerebelli.
foetus: the developing mammal in utero; in Man, after the 2nd month in utero, adjective - foetal or fetal.
frontal: adjective, Latin frontis = of the forehead, or coronal.
fundiform: adjective, Latin fundus = bottom or base (cf. fundamental), hence, sling-shaped.
fundus: Latin = bottom or base. (But note that the fundus of the stomach and uterus are at the top, and the fundus of the eye and of the bladder are posterior!).
funiculus: diminutive of Latin funis = cord (used usually for bundles of nerve fibres).
fusiform: adjective, Latin fusus = spindle, hence, spindle-shaped.