Code of Federal Regulations Title 21. Food and Drugs § 21.333.203 Definitions

(a) Antifungal. A drug which inhibits the growth and reproduction of fungal cells and decreases the number of fungi present.

(b) Athlete's foot. An infection of the feet caused by certain dermatophytic fungi.

(c) Dermatophyte. A fungus that invades and lives upon the skin or in the hair or nails.

(d) Fungus. Any of a large division of plants, including dermatophytes, yeasts, and molds, characterized by a simple cell structure and the absence of chlorophyll.

(e) Jock itch. A chronic and recurrent infection caused by certain dermatophytic fungi;  affects the upper, inner thighs and sometimes extends to the groin and the pubic area;  the condition most frequently occurs in men, but may also occur in women.

(f) Ringworm. A skin infection caused by certain dermatophytic fungi.