Etymology From Eire + -ish. See also the usage note below.
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Dated, Proscribed of the state called Eire or the Republic of Ireland, as distinct from the island of Ireland
The new Eirish constitution never mentions the Anglo-king or Empire. ... An Eirish Supreme Court takes the place of the British Privy Council as haven of last resort.1937 July 24, “Eire is airy”, in The Digest Review of Reviews; incorporating The Literary Digest, page 9:
I wonder whether there is an adjective governing the word "Eire." We have been listening to the Prime Minister and the hon. Member above the Gangway and the hon. Member for Down (Sir D. Reid) and I hoped that I should hear an adjective corresponding to the word "Eire." I do not know whether I should be in order if I said "Eirish."1938 May 5, Graham White Eire (Confirmation of Agreements) Bill. HC Deb vol 335 c1090
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So far as the appointment of Consuls or even Ministers is concerned, His Majesty holds the same position for Eire as he does for Canada or South Africa. The only variance is that in the Eirish Act "King" is spelt with a small "k."1938 December 17, "Obiter Dicta: Eire Abroad" The Law Journal (London) vol.86 no.3805 p.416
The Board must realise that we may not be able to obtain satisfaction, as the question of Eirish neutrality raises political issues which have not yet been faced, and which the First Lord is not certain he can solve.1939 November 5, Winston Churchill; cited in Winston Churchill (1950, 3rd ed.) The Second World War; Vol.1: The gathering storm (London: Cassell) p.382
It happened that in a talk for the Overseas Service he referred to Dublin as 'the Irish capital'. The disc had been played by mistake on the Home Service and so [George] Marshall had heard it. Johnston parried Marshall’s complaint by asserting that what he really said was 'It is the Eirish capital'!1941 Denis Johnson, cited in Theodor Fontane, 1989,Delusions, confusions; and the Poggenpuhl family (New York: Continuum) →ISBN) p.121
It is Mr Roosevelt’s first really stupid mistake. The Eirish leader, with all Ireland, Protestant and Catholic, behind him, Mr de Valera will tell the President, in fact, to go to hell.1944 April 1, George Bernard Shaw, "Eamon de Valera and the Second World War" Forward (Glasgow) -- reprinted in The matter with Ireland (University Press of Florida, 2001) p.326
Etymology From Eire + -ish. See also the usage note below.
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Historical A proposed simplified standardised dialect of Irish for use by English-speaking learners
Every Celt under seventy can acquire Eirish ... the supporters of Irish mean to press for the official recognition of Eirish in the schools of Northern and Southern Ireland1936, Diarmuid O Murcu, Minstrel of Eirish: being some of the best known hymns and songs done into standard Irish with originals, Waterford:
c.1940 Diarmuid O Murcu, Irish made easy (Eirish); a self instructor for the adult
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1952 Standard Irish vocabulary: an English-Eirish vocabulary containing about 2,000 of the most useful Irish words, and including the basic English vocabulary (Eirish Society: Dublin)