I

nouns

a nonmetallic element belonging to the halogens; used especially in medicine and photography and in dyes; occurs naturally only in combination in small quantities (as in sea water or rocks)
I, atomic number 53, iodin, iodine
the smallest whole number or a numeral representing this number
"he has the one but will need a two and three to go with it"; "they had lunch at one"
1, I, ace, one, single, unity
the 9th letter of the Roman alphabet
I, i