Familiarization (n.)
definition: The act or process of making familiar; the result of becoming familiar; as
Familiarization with scenes of blood.
Familiarization is a 15 letter word that begins with a F and ends in an N

Fashionableness (n.)
definition: State of being fashionable.

Fashionableness is a 15 letter word that begins with a F and ends in an S

Father longlegs
definition: See Daddy longlegs
2.
Father longlegs is a 15 letter word that begins with a F and ends in an S

Fellow-commoner (n.)
definition: A student at Cambridge University
England who commons or dines at the Fellow's table.
Fellow-commoner is a 15 letter word that begins with a F and ends in an R

Fellow-creature (n.)
definition: One of the same race or kind; one made by the same Creator.

Fellow-creature is a 15 letter word that begins with a F and ends in an E

Flibbertigibbet (n.)
definition: An imp.

Flibbertigibbet is a 15 letter word that begins with a F and ends in a T

Flowery-kirtled (a.)
definition: Dressed with garlands of flowers.

Flowery-kirtled is a 15 letter word that begins with a F and ends in a D

Flying squirrel
definition: One of a group of squirrels
Of the genera Pteromus and Sciuropterus having parachute-like folds of skin extending from the fore to the hind legs which enable them to make very long leaps.
Flying squirrel is a 15 letter word that begins with a F and ends in an L

Forcible-feeble (a.)
definition: Seemingly vigorous
But really weak or insipid.
Forcible-feeble is a 15 letter word that begins with a F and ends in an E

Fore-topgallant (a.)
definition: Designating the mast
Sail yard etc. above the topmast; as the fore-topgallant sail. See Sail.
Fore-topgallant is a 15 letter word that begins with a F and ends in a T

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