
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