Ir vs iridium

Ir and iridium both are nouns.

Word	Noun	Adjective	Verb	Adverb
Ir	Yes	No	No	No
iridium	Yes	No	No	No

As nouns, Ir and iridium are synonyms defined as:

Ir and iridium: a heavy brittle metallic element of the platinum group; used in alloys; occurs in natural alloys with platinum or osmium

Other synonyms of Ir include atomic number 77.

Ir (noun)	iridium (noun)
a heavy brittle metallic element of the platinum group; used in alloys; occurs in natural alloys with platinum or osmium	a heavy brittle metallic element of the platinum group; used in alloys; occurs in natural alloys with platinum or osmium