F vs f

F and f both are nouns.

Word	Noun	Adjective	Verb	Adverb
F	Yes	No	No	No
f	Yes	No	No	No

As nouns, F and f are synonyms defined as:

F (noun)	f (noun)
the 6th letter of the Roman alphabet	the 6th letter of the Roman alphabet
the capacitance of a capacitor that has an equal and opposite charge of 1 coulomb on each plate and a voltage difference of 1 volt between the plates
a degree on the Fahrenheit scale of temperature
a nonmetallic univalent element belonging to the halogens; usually a yellow irritating toxic flammable gas; a powerful oxidizing agent; recovered from fluorite or cryolite or fluorapatite