Formication. A sensation like that of the creeping of ants.

Formula. Prescriptions; given forms.

Fossa. A depression in a bone.

Frenum. A bridle; a binding or restraining membrane.

Fundus. The larger part of a cone shaped organ.

Funis. The umbilical cord; the naval string.

Furuncle. A boil.

Gall-stones. Concretions formed from the bile.

Ganglion. An enlargement in the course of a nerve.

Gangrene. Partial death; mortification.