1. (noun)iodine, iodin, I, atomic number 53 a nonmetallic elementbelonging 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)
2. (noun)one, 1, I, ace, single, unity the smallest wholenumber 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"
Definition of 'I':
