The modern Irish Éire evolved from the Old Irish word Ériu, which was the name of a Gaelic goddess. Ériu is generally believed to have been the matron goddess of Ireland, a goddess of sovereignty, or simply a goddess of the land. The origin of Ériu has been traced to the Proto-Celtic reconstruction *Φīwerjon- (nominative singular Φīwerjū < Pre-Proto-Celtic -jō). This suggests a descent from the Proto-Indo-European reconstruction *piHwerjon-, likely related to the adjectival stem *piHwer- (cf. Sanskrit pīvan, pīvarī and pīvara meaning "fat, full, abounding"). This would suggest a meaning of "abundant land".
This Proto-Celtic form became Īweriū or Īveriū in Proto-Goidelic. It is highly likely that explorers borrowed and modified this term. During his exploration of northwest Europe (circa 320 BCE), Pytheas of Massilia called the island Ierne (written Ἰέρνη). In his book Geographia (circa 150 CE), Claudius Ptolemaeus called the island Iouernia (written Ἰουερνία). Based on these historical accounts, the Roman Empire called the island Hibernia.
Thus, the evolution of the word would follow as such:
- Proto-Celtic *Φīwerjon- (nominative singular *Φīwerjū)
A 19th century proposal, which does not follow modern standards of etymology, derives the name from Scottish Gaelic:
- ì (island) + thairr (west) + fónn (land), which together give ì-iar-fhónn, or "westland isle"
Difference between Éire and Erin 
While Éire is simply the name for Ireland in the Irish language, and sometimes used in English, Erin is a common poetic name for Ireland, as in Erin go bragh. The distinction between the two is one of the difference between cases of nouns in Irish. Éire is the nominative case, the case that (in the modern Gaelic languages) is used for nouns that are the subject of a sentence i.e. the noun that is doing something as well as the direct object of a sentence. Erin derives from Éirinn (pronounced [ˈeːɾʲɪɲ] ( listen)), the Irish dative case of Éire, which has replaced the nominative case in Déise Irish (and some non-standard sub-dialects elsewhere), in Scottish Gaelic (where the usual word for Ireland is Èirinn) and Manx (a form of Gaelic), where the word is spelled Nerin, with the initial n- is probably in origin a fossilisation of the preposition in/an "in" (cf. Irish in Éirinn, Scottish an Èirinn/ann an Èirinn "in Ireland"). The genitive case Éireann is used in the Gaelic forms of the titles of companies and institutions in Ireland e.g. Iarnród Éireann (Irish Rail), Dáil Éireann (Irish Parliament) or Poblacht na hÉireann (The Republic of Ireland).
Éire as a state name 
Article 4 of the Irish constitution adopted in 1937 states that Éire is the name of the state, except in the English language, where it is Ireland. The Constitution's English-language preamble also described the population as "We, the people of Éire". Despite the fact that Article 8 designated Irish as the "national" and "first official" language, Éire has to some extent passed out of everyday conversation and literature, and the state is referred to as Ireland or its equivalent in all other languages. The name "Éire" has been used on Irish postage stamps since 1922; on all Irish coinage (including Irish euro coins); and together with "Ireland" on passports and other official state documents issued since 1937. "Éire" is used on the Seal of the President of Ireland. Before the 1937 Constitution, "Saorstát Éireann" (the Irish name of the Irish Free State) was generally used.
In 1922–1938 the international plate on Irish cars was "SE". From 1938 to 1962 it was marked "EIR", short for Éire. In 1961 statutory instrument no. 269 allowed "IRL", and by 1962 "IRL" had been adopted. Irish politician Bernard Commons TD suggested to the Dáil in 1950 that the government examine "the tourist identification plate bearing the letters EIR ... with a view to the adoption of identification letters more readily associated with this country by foreigners". "EIR" is also shown in other legislation such as the car insurance statutory instrument no. 383 of 1952 and no. 82 of 1958.
Use of Eire in Britain and the US 
In 1938 the British government provided in the Eire (Confirmation of Agreements) Act 1938 that British legislation could henceforth refer to the Irish Free State as "Eire" (but not as "Ireland"). The 1938 Act was repealed in 1981, and the term is now rarely used in modern British English. It is still seen on some airport signage in 2011: Liverpool John Lennon Airport has an arrivals area for "Eire and Channel Islands".
The misspelling of their country's name "Éire" as Eire is generally deplored by Irish language speakers, because "eire" means - a burden, load or encumbrance, which gives a slightly pejorative nuance to the name of the island and/or the state.
Other uses 
Éire has also been incorporated into the names of Irish commercial and social entities, such as Eircom Group plc (formerly "Telecom Éireann") and its former mobile phone network, Eircell. In 2006 the Irish electricity network was devolved to EirGrid. The company "BetEire Flow" (eFlow), named as a pun on "better", is a French consortium running the electronic tolling system at the West-Link bridge west of Dublin. According to the Dublin Companies Registration Office in 2008, over 500 company names incorporate the word Éire in some form.
- Proto-Celtic—English lexicon
- Mallory, J.P. and D.Q. Adams, ed. Encyclopedia of Indo-European Culture. London: Fitzroy Dearborn Pub., 1997, p. 194
- Forbes, John (1848), The Principles of Gaelic Grammar (2nd ed.), Edinburgh: Oliver and Boyd, p. 160, "The Celitc words ì, inns, an island, will forma key to the etymology of the names of many insular and peninsular places in the world; as, Ile, Islay. Jura or Iura, Jura. Uist, Uist, Inchkeith, isle of Keith. Eireinn, or Eirionn, ì-iar-fhónn, wetland isle; Ireland."
- "Constitution of Ireland". Office of the Houses of the Oireachtas. Retrieved on 14 March 2007
- Hamilton-Bowen, Roy (2009). In Roy Hamilton-Bowen. Hibernian Handbook and Catalogue of the Postage Stamps of Ireland. Rodgau, Germany: Rodgau Philatelic Service GmbH.
- SI 269 of 1961:"...the letters EIR are used to indicate the name of the State but the letters IRL may be substituted therefor."
- "Dáil Éireann – Volume 119 - 22 March, 1950 – Ceisteanna—Questions. Oral Answers. – Motor Identification Letters". Historical-debates.oireachtas.ie. 1950-03-22. Retrieved 2010-03-26.
- "SI 82 of 1958 text". Irishstatutebook.ie. 1959-12-31. Retrieved 2010-03-26.
- "SI 383 of 1952". Irishstatutebook.ie. Retrieved 2010-03-26.
- John Wilson (1996). Understanding Journalism: A Guide to Issues. Routledge. p. 269. ISBN 978-0-415-11599-5.
- McBain A., An Etymological Dictionary of the Gaelic Language; Clark Constable, Edinburgh (1982) ISBN 0-901771-68-6; seen online 20 Aug 2011
- The Eire Society of Boston's history page on-line (seen on 25 August 2011)
- "eircom homepage". Eircom.ie. 2006-11-29. Retrieved 2010-03-26.
- "National Roads Authority statement 2007". Nra.ie. Retrieved 2010-03-26.
- "CRO search page". Cro.ie. Retrieved 2010-03-26.
- Comment on ScaryÉire
- "Some recent social changes are not easily linked with the Tiger per se" (PDF). Retrieved 2010-03-26.
|Look up Éire in Wiktionary, the free dictionary.|
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