From Old Irish Ériu, from Proto-Celtic *ɸīwerjō (compare Middle Welsh Iwerd (“Irish Sea”)), from Proto-Indo-European *piHweryon-, likely related to *fat (compare Ancient Greek πίειρα (píeira, “fertile”), Sanskrit पीवरी (pī́varī, “fat, rich”)).
- IPA: [ˈeːɾʲə]
Proper noun 
- Ireland (both the island and the republic)
- Fifth declension
Forms with the definite article
|Radical||Eclipsis||with h-prothesis||with t-prothesis|
|Note: Some of these forms may be hypothetical. Not every
possible mutated form of every word actually occurs.
Usage notes 
Éire is one of the few nouns in Irish with a distinct dative case in the standard language.