Fork.  A pickpocket.  Let us fork him; let us pick his
  pocket.—­’The newest and most dexterous way, which is,
  to thrust the fingers strait, stiff, open, and very quick,
  into the pocket, and so closing them, hook what can
  be held between them.’  N.B.  This was taken from a
  book written many years ago:  doubtless the art of picking
  pockets, like all others, must have been much improved
  since that time.

Forlorn Hope.  A gamester’s last stake.

Fortune hunters.  Indigent men, seeking to enrich
  themselves by marrying a woman of fortune.

Fortune teller, or cunning man.  A judge, who tells
  every prisoner his fortune, lot or doom.  To go before the
  fortune teller, lambskin men, or conjuror; to be tried at
  an assize.  See lambskin men.

Foul.  To foul a plate with a man, to take a dinner with him.

Foul-mouthed. Abusive.

Foundling.  A child dropped in the streets, and found, and
  educated at the parish expence.

FOUSIL.  The name of a public house, where the
  Eccentrics assemble in May’s Buildings, St. Martin’s Lane.

Fox.  A sharp, cunning fellow.  Also an old term for a
  sword, probably a rusty one, or else from its being dyed red
  with blood; some say this name alluded to certain swords
  of remarkable good temper, or metal, marked with the
  figure of a fox, probably the sign, or rebus, of the maker.

Fox’s paw.  The vulgar pronunciation of the French
  words faux pas.  He made a confounded fox’s paw.

Foxed. Intoxicated.

FOXEY.  Rank.  Stinking.

Foxing A boot.  Mending the foot by capping it.

FOYST. A pickpocket, cheat, or rogue.  See WOTTON’S gang.

To FOYST. To pick a pocket.

FOYSTED in.  Words or passages surreptitiously interpolated
  or inserted into a book or writing.

Fraters.  Vagabonds who beg with sham patents, or briefs,
  for hospitals, fires, inundations, &c.

Free.  Free of fumblers hall; a saying of one who cannot
  get his wife with child.

Free and easy Johns.  A society which meet at the Hole
  in the Wall, Fleet-street, to tipple porter, and sing bawdry.

Free BOOTERS.  Lawless robbers and plunderers:  originally
  soldiers who served without pay, for the privilege of
  plundering the enemy.

Freeholder.  He whose wife accompanies him to the alehouse.

Freeman’s Quay.  Free of expence.  To lush at Freeman’s
  Quay; to drink at another’s cost.

Freeze.  A thin, small, hard cider, much used by vintners
  and coopers in parting their wines, to lower the price of
  them, and to advance their gain.  A freezing vintner; a
  vintner who balderdashes his wine.