[finders keepers] or [finders keepers, losers weepers] {informal} Those who find […]

[fine feathers do not make fine birds] {literary} A person who […]

[fine kettle of fish] See: [KETTLE OF FISH].

[fine-tooth comb] {n. phr.} Great care; careful attention so as not […]

[finger] See: [BURN ONE'S FINGERS], [CROSS ONE'S FINGERS] or [KEEP ONE'S […]

[finger in the pie] also [finger in every pie] {n. phr.}, […]

[fingertip] See: [AT ONE'S FINGERTIPS].

[finish up] See: [END UP] (4).

[fire] See: [BALL OF FIRE], [BETWEEN THE DEVIL AND THE DEEP […]

[firebug] {n.} An arsonist; one who willfully sets fire to property. […]