Fertilization: takes place when a spermatozoön enters through the micropyle of an ovum and unites with the cell nucleus: loosely applied like copulation or to its completion.
Festivus: variegated with bright colors.
Festooned: arranged in loops as if hung from nails.
Fibre: a thread-like structure of any tissue.
Fibrilla: rod or sliver-like nerve elements, often grouped like a bundle of short threads.
Fibrin: a proteid compound making up a large part of the muscular tissue: also found in blood and other body liquids.
Fibrinogen: a proteid substance of the blood and other body fluids, concerned in the production of fibrin.
Fibroin: a chemical compound found in silk, cobwebs and the like.
Fifth longitudinal vein: Diptera (Will.); = media 3 (Comst.).
Filament: a thread: a long slender process of equal diameter throughout: an elongated appendage.