Noun: Icelander(s)
Adjective: Icelandic
Noun: Indian(s)
Adjective: Indian
Noun: Indonesian(s)
Adjective: Indonesian
Noun: Iranian(s)
Adjective: Iranian
Noun: Iraqi(s)
Adjective: Iraqi
Noun: Irishman(men), Irishwoman(women), Irish (collective plural)
Adjective: Irish
Noun: Manxman (men), Manxwoman (women)
Adjective: Manx
Noun: Israeli(s)
Adjective: Israeli
Noun: Italian(s)
Adjective: Italian