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| Name. |
County. |
Meaning. |
| oooooooooooooooooooo | ooooooooooooooo | |
| Mace | Mas [Mauce], the thigh, a long low hill. | |
| Mackan | Mackanagh, Macknagh, Mackney; a place producing parsnips (meacan, a parsnip). | |
| Macosquin | Co Derry | Corrupted from Magh-Cosgrain [Macosgran], "F. M., Cosgran's plain. |
| Maghera | Machaire, a plain. Maghera in Down and Maghera in Derry, are both contracted from Machaire-ratha [Maghera-raha], the plain of the fort. | |
| Magherabeg; | Lttle plain. | |
| Magheraboy | Yellow plain. | |
| Magheracloone | The plain of the cloon or meadow. | |
| Magheraculmoney | The plain of the back (cul) of the shrubbery. | |
| Magheradrool | Co Down | Machaire-eadarghabhal [Maghera- addrool], the plain between the (river) forks(eadar, between; and gabhal). See Addergoole. |
| Magherahamlet | Co Down; the plain of the Tamlaght or plague monument. See Tallaght. | |
| Magheramenagh | Middle plain (meadhonach). | |
| Magheramore; | Great plain. | |
| Magherareagh | Grey plain (riabhach). | |
| Maghery | A form of Maghera, a plain. | |
| Magunihy | Co Kerry | Barony of, in Kerry; Magh-gCoincinne[Magunkinny], F. M., the plain of the O'Conkins. |
| Mahee island | Co Down | In Strangford Lough; the island of St. Mochaei [Mohee], bishop, a disciple of St. Patrick, and the founder of Nendrum. |
| Maigue | Co Limerick | A river in Limerick ; called Maigh in the annals, i.e., the river of the plain. |
| Mallow | Co Cork | Called in the Annals Magh-Ealla [Moyallo], the plain of the river Allo, which was anciently the name of that part of the Blackwater flowing by the town. See Duhallow. |
| Manulla | Co Mayo | Magh-Fhionnalbha [Mah-Innalva], Hy. F., Finalva's plain. |
| Massareene | Co Antrim | Mas-a'-rioghna [Massareena], the queen's hill. |
| Maul | Meall, a lump, a hillock. | |
| Maum | Madhm [Maum], a high mountain pass. | |
| Maumturk | The pass of the boars (torc). | |
| Maw | Magh, a plain. | |
| Maynooth | Magh-Nuadhat [Ma-nooat], F. M., Nuadh-afs plain; from Nuadhat, king of Leinster, foster-father to Owen More king of Munster. See Bear. | |
| Mayo | Magh-eo [Ma-o], the plain of the yews. Full name Magheo-na-Saxan, F. M., Mayo of the Saxons, from a number of English monks settled there in the seventh century, by St. Colman, an Irish monk, after he had retired from the see of Lindisfarne. | |
| Meelick | Miliuc [Meeluck], F. M., low marshy ground. | |
| Meen | A mountain meadow | |
| Meenadreen | The mountain meadow of blackthorns. | |
| Meenkeeragh | Mountain meadow of the sheep. | |
| Milleen | A little hillock. See Maul. | |
| Moan | Mom [mone], a bog. See Mon. | |
| Moanduff | Black bog. | |
| Moanmore | Great bog. | |
| Moanroe | Red bog. | |
| Moanvane | Moanvaun; Moin-bhan, white bog. | |
| Moat; | Mota, a high mound. | |
| Moate | Co Westmeath | From the great mound at the village; full name Moategranoge, the moat of Graine-og or young Grace, who, according to tradition, was a Munster princess. |
| Mocollop | The plain (magh) of the collops or cattle | |
| Modeshill | Magh-deisiol [Ma-deshil], southern plain. | |
| Mogeely | Magh-Ile, F. M., the plain of Ile or Ely. | |
| Moher | See Cliffs of Moher. | |
| Mohill | Maethail [Mwaybill], soft or spongy land; from maeth, soft. | |
| Moig | Moigh; forms of Magh, a plain. | |
| Moira | Magh-rath, F. M., the plain of the forts. | |
| Mon | A bog. See Moan. | |
| Monabraher | Monambraher, Monamraher; Moin-na-mbrathar, F. M., the bog of the friars. | |
| Monagay | Co Limerick | The bog of the goose (gedh); from wild geese. |
| Monaghan | Muineachon, F. M., a place full of little hills or brakes (muine). | |
| Monamintra | Co Waterford; | Moin-na-mbaintreabhaigh [Monamointree], the bog of the widows. |
| Monard | High bog. | |
| Monasteranenagh | Co Limerick | Mainister-an-aenaigh [Monasteraneany], F. M., the monastery of the fair, Anciently called Aenach-beag, little fair. |
| Monasterboice | Co Louth | The monastery of St. Boethius or Buite, who founded it in the sixth century. |
| Monasterevin | The monastery of St. Evin, the founder a contemporary of St. Patrick. | |
| Monasteroris | Co Offaly | In King's County; Mainister-Fheorais, [orish: F aspirated and omitted-see p. 2], the monastery of Mac Feorais or Bermingham, who founded it in A.D. 1325. |
| Monear | A meadow. | |
| Moneen | A little bog (moin). | |
| Money | Muine [munny], a shrubbery. | |
| Moneydorragh | Muine-dorcha, dark or gloomy shrubbery. | |
| Moneyduff; | Muine-dubh, black shrubbery. | |
| Money gall; | The shrubbery of the Galls or foreigners. | |
| Moneygorm | Muine-gorm, blue shrubbery. | |
| Moneymore | Great shrubbery. | |
| Monivea | Co Galway | Muine-an-mheadha [Money-an-va], F. M., the shrubbery of the mead, a kind of drink. |
| Monroe | Moin-ruadh, red bog. | |
| Montiagh | Montiaghs; Mointeach, a boggy place. | |
| Morgallion | A branch of the Gailenga (see Gallen), settled in Leinster, and a portion of them gave name to the territory of Mor-Gailenga or the great Gailenga, now the barony of Morgallion in Meath. | |
| Mothel | Mothell; same as Mohill. | |
| Mountmellick | The old anglicised name is Montiagh-meelick, the bogs or boggy land of the meelick or marsh. See Montiagh and Meelick. | |
| Mourne | Co Down | Mountains in Down. The ancient name was Beanna Boirche [Banna-Borka], F. M., the peaks of the shepherd Boirche, who herded on these mountains the cattle of Ross, king of Ulster in the third century. About the middle of the twelfth century, a tribe of the Mac Mahons from Cremorne (see Cremorne), settled in the south of the present county of Down, and gave their tribe name of Mughdhorna [Mourna], to the barony of Mourne, and to the Mourne mountains. |
| Movilla | Co Down | Magh-bhile [Ma-villa], O'O. Cal, the plain of the ancient tree. |
| Moville | Co Donegal | Magh-bhile [Ma-villa], O'O. Cal, the plain of the ancient tree. |
| Moy | Magh [mah], a plain. | |
| Moyacomb | Co Wicklow | Magh-da-chon [Moy-a-con], F. M., the plain of the two hounds. |
| Moyaliff | Co Tipperary | Magh-Ailbhe [Moyalva], F. M., Ailbhe's or Alva's plain. Moyard; high plain. |
| Moyarget | Magh-airgid, the plain of silver. | |
| Moyarta | Co Clare | Magh-fherta (fh silent: see p. 2), the plain of the grave. |
| Moycullen | Co Galway | The plain of holly. |
| Moydow | Co Longford | Magh-dumha [Moy-dooa], F. M., the plain of the burial mound. |
| Moygawnagh | Co Mayo | Written in the Book of Lecan, Magh-gamhnach) the plain of the milch cows. |
| Moyglass | Green plain. | |
| Moygoish | The descendants of Colla Uais (see Cremorne), were called Ui mic Uais [Ee-mic-Oosh]; a portion of whom were settled in Westmeath, and gave their name to the barony of Moygoish. | |
| Moyle | Mael, a bald or bare hill. | |
| Moylough | The plain of the lake. | |
| Moymore | Great plain. | |
| Moynalty | Co Meath | Magh-nealta [Moynalta], the plain of the flocks (ealta). |
| Moyne | Maighin [Moin], a little plain. | |
| Moynoe | Co Clare | Same as Mayo: the n is a grammatical accident. |
| Moynure | The plain of the yew (iubhiar). | |
| Moyrus | The plain of the ros or peninsula. | |
| Moys | i.e. plains; from magh. | |
| Muckamore | Co Antrim | Magh-comair [Ma-cummer], F. M., the plain of the cummer or confluence (of the Six mile Water with Lough Neagh). |
| Muckanagh | Muckenagh; Muiceannach, a resort of pigs; a place where pigs used to feed or sleep (from muc). | |
| Muckelty | Mucker, Muckera, Muckery; the same as Muckanagh. | |
| Mucklagh | Muclach, same as Muckanagh. | |
| Muckinish | Pig island. | |
| Muckloon | Mucklone, Mucklin; Muc-chluain, pig meadow. | |
| Muckno | Co Monaghan | Mucshnamh [Mucknauv], F. M., the swimming place (snamh) of the pigs; the place where pigs used to swim across the little lake. |
| Muckross | The peninsula of the pigs. | |
| Muff | A corruption of Magh, a plain. | |
| Muing | A sedgy place. | |
| Mullacrew | Co Louth; Mullach-craeibhe [Mullacreeva], the summit of the spreading tree. | |
| Mullagh | Mullach, a summit. | |
| Mullaghareirk | Co Limerick | Mountains near Abbeyfeale in Limerick; Mullach-a'-radhairc [rirk], the summit of the prospect. |
| Mullaghbane | White summit. | |
| Mullaghhoy | Yellow summit. | |
| Mullaghhrack | Speckled summit. | |
| Mullaghdoo | Mullaghduff; black summit. | |
| Mullaghglass | Green summit. | |
| Mullaghmeen | Mullach-min, smooth summit. | |
| Mullaghmore | Great summit. | |
| Mullaghroe | Mullach-ruadh, red summit. | |
| Mullan | Mullaun; a little mullach or summit. | |
| Mullans | Little summits. | |
| Mullen | Mullin; Muileann [mullen], a mill. | |
| Mullinahone | Co Tipperary | Muileann-na-huamhainn [Mullinahooan], the mill of the cave (uamha); from a cave near the village through which the little river runs. |
| Mullinavat | Co Kilkenny | Muilenn-a'-bhata, the mill of the stick. |
| Mully | Mullach, a summit. | |
| Multyfarnham | Co Westmeath | Muilte-Farannain [Mul-ty-Farannan], Farannan's mills (muilenn, plural muilte). |
| Munster | Old Irish name Mumhan [Mooan], which, with `ster' added (see Leinster), forms Mughan-ster [Moonster] or Munster. | |
| Murragh | Murreagh; Murbhach [Murvagh], a flat marshy piece of land by the sea. | |
| Murrow | of Wicklow; same as Murragh. | |
| Muskerry | The people descended from Carbery Musc, son of Conary II. (see Corkaguiny), were called Mus-craidhe [Muskery: O'Dugan]; of these there were several tribes, one of which gave name to the two baronies of Muskerry in Cork. | |
| Myshall | Co Carlow | Muigh-iseal [Mweeshal], low plain. |
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