Here are the definitions for the letter "f"

Fermentation

Conversion of sugars into ethyl alcohol and carbon dioxide, through the action of yeast.

Filtration

The removal of impuritiesin the wort or beer. Yeast in suspension is a typical target.

Final specific gravity

See Specific gravity.

Fining

A substance to facilitate beer clarification.

Finish

The lingering taste sensation that accompanies swallowing.

Flemish Style Brown Ale.

These are complex dark beers most closely associated with the town of Oudenaarde in Flanders. The authentic examples are medium to full bodied beers that are influenced by a number of factors: high bicarbonate in the brewing water to give a frothy texture; a complex mix of yeasts and malts; blending of aged beers; and aging in bottle before release. In the best examples, the flavor profile is reminiscent of olives, raisins, and brown spices and could be described as 'sweet and sour.' These beers are not hop-accented and are of low bitterness.

Fruity

Tasting term describing the flavor and aroma of bananas, strawberries, apples, and/or citrus notes resulting from high temperature fermentation and top-fermenting yeast strains.