O'Connell, Peter (Ó Conaill, Peadar) (1755–1826), schoolmaster and lexicographer, was born at Carne, Killimer, Co. Clare (a townland latterly designated as Carrowdotia, on the Shannon estuary 8 km east of Kilrush), one of four sons and two daughters of Tadhg Ó Conaill and Áine Ó Conaill; his mother had a small farm. Said to have ‘manifested a greater love for books than for the land’ (Gleeson, 343), he was educated in a nearby hedge school, possibly that owned by Seán Ó Cinnéide at Burrane. Growing up in a noted centre of Gaelic scholars and poets, he developed an early interest in poetry, and became friendly with Eoghan O'Curry, the father of Eugene O'Curry (qv), often staying in the O'Curry home at Doonaha, Co. Clare. He collected poetry of the Munster school, including poems in Irish by John Lloyd (qv) and Seán Ó Tuama (qv), and he transcribed the Ossianic tale ‘Bás an mhacaoimh mhóir’ for the RIA in the 1780s. After the death of his mother, he worked as a weaver in Tullabrack, Co. Clare (1785–7), then travelled to Dublin, where he met Theophilus O'Flanagan (qv), for whom he transcribed manuscripts in the RIA. In the same year (1787), he also met the scholar Charles O'Conor (qv), and performed similar work for him at his home in Bellanagare, Co. Roscommon.
Conceiving the idea of compiling a dictionary of the Irish language, he went to the north of Ireland to collect vocabulary. His first journey to Scotland (1787) may have been assisted financially by the MacDonnell family of Kilkee, Co. Clare, who were known to be patrons of Irish scholars. While living briefly in Co. Kerry in 1788, O'Connell planned to establish a mathematical school in a church in Brosna, where he was known as ‘teacher of the mathematics in Kerry’. He went to Dublin in May 1788, but became ill and returned to his family in Co. Clare. Returning to Dublin in 1790, he spent much time in the RIA discussing the brehon laws, but was unable to secure a position in the academy. He studied in TCD in 1791, and transcribed ‘Quatrains in Irish on Irish families: a tract on Irish orthography’, a manuscript now held in Cambridge University Library. He spent most of 1792 in Scotland, staying in Culross, a village near Perth. He was in Newcastle in 1793, and also spent time in the Scottish highlands, the Hebrides, the Orkney islands, and Wales. Studying the comparative forms of Gaelic speech, he also acquired a thorough knowledge of Scottish place names. A Scottish grammatical list, written in his hand, is in NUI Maynooth. O'Connell was back in Ireland in 1794, and stayed in Killeedy, Co. Limerick, in 1795. He was in Dublin in 1797, where he wrote, and stayed with the Chevalier (Thomas) O'Gorman (qv), for whom he translated antique Irish books.
Settling down in his native Clare (1798–1812), O'Connell continually revised his Irish–English dictionary, and for two years had a hedge school at Money Point (1803–5). He then spent ten years in Limerick city (1812–22), living in the home of Dr Simon O'Reardon, who had founded a Gaelic society. He spent 40 years compiling and arranging the manuscript of his Irish–English dictionary, studied ancient Irish manuscripts, and ran a school in the city; one of his pupils was Malachy O'Curry, a brother of Eugene, who assisted him in the preparation of his manuscript. In 1813 William Howly, treasurer of the Limerick Society for the Revival of Ancient Irish Literature, invited subscriptions for the publication of ‘A dictionary of the Irish language’ by Peter O'Connell. O'Reardon (d. 1821) planned to help in the publishing of O'Connell's manuscript, but the two men quarrelled over the matter in 1819; thereafter, O'Connell returned to his brother's farm at Carne, and opened a school in nearby Moyne. He died unmarried on 24 February 1826, and was buried in the same grave as Ellie Hanley (qv), the ‘colleen bawn’, in Burrane cemetery, Killimer, Co. Clare; when, after her murder in 1819, the body had washed ashore at Carne, O'Connell had given permission for the burial in his plot.
Shortly after O'Connell's death, his nephew Anthony O'Connell took the manuscript of the dictionary to Tralee assizes and showed it to Daniel O'Connell (qv), who dismissed it scornfully, reputedly saying that the compiler was ‘an old fool to have spent so much of his life on so useless a work’ (Buckley, 201). Anthony then pawned the manuscript for ten shillings in Tralee, but Eugene O'Curry obtained the ticket from him, and retrieved the document. In the meantime, James Hardiman (qv) had gone to Clare to bargain for the manuscript, and he demanded it from O'Curry, assuring him that he would place the work in Maynooth college. However, Hardiman sold the manuscript to the British Museum (latterly the British Library), where it remains, an act for which O'Curry found it very hard to forgive him. Though the manuscript has never been printed, John O'Donovan (qv) made a two-volume copy, now held in TCD library; other copies are in the RIA and the NLI. Praised by contemporary scholars as the best Irish dictionary then available, O'Connell's manuscript, which he spent forty years researching and compiling, was used extensively by Patrick Dinneen (Pádraig Ó Duinnín) (qv) in the preparation of his revised Irish–English dictionary published by the Irish Texts Society, London (1927), and is still consulted by editors of Irish-language texts.