air vs O

air and O both are nouns.

Word	Noun	Adjective	Verb	Adverb
air	Yes	No	Yes	No
O	Yes	No	No	No

air (noun)	O (noun)
travel via aircraft	the blood group whose red cells carry neither the A nor B antigens
a distinctive but intangible quality surrounding a person or thing	the 15th letter of the Roman alphabet
a succession of notes forming a distinctive sequence	a nonmetallic bivalent element that is normally a colorless odorless tasteless nonflammable diatomic gas; constitutes 21 percent of the atmosphere by volume; the most abundant element in the earth's crust
medium for radio and television broadcasting
the region above the ground
the mass of air surrounding the Earth
a slight wind (usually refreshing)
a mixture of gases (especially oxygen) required for breathing; the stuff that the wind consists of
once thought to be one of four elements composing the universe (Empedocles), associated with the humour blood

air (verb)	O (verb)
expose to cool or cold air so as to cool or freshen
expose to warm or heated air, so as to dry
make public
broadcast over the airwaves, as in radio or television
be broadcast
expose to fresh air