WordNet sense 1 (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):

WordNet sense 2 (a degree on the Fahrenheit scale of temperature):

WordNet sense 3 (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):

WordNet sense 4 (the 6th letter of the Roman alphabet):