Dalkey Island near Dublin. The Irish name is Delg-inis (O’C. Cal.), thorn island; which the Danes, who had a fortress on it in the tenth century, translated to the present name, by changing Delg into their word Dalk, a thorn; and substituting the northern word ey, an island, for inis.

Dangan; Daingean [dangan], a fortress.

Dangandargan in Tipperary; Dargan’s fortress.

Darragh; a place producing oaks (dair).

Darraragh, Darrery; an oak forest, a place abounding in oaks (Dairbhreach).

Dawros; Damhros, the peninisula of oxen (damh and ros).

Deelis, Deelish; Duibh-lios [Divlis], black lis or fort.

Delvin. There were formerly seven tribes called Dealbh­na [Dalvăna], descended and named from Lugh­aidh Dealbhaeth [Lewy Dalway], who was the son of Cas mac Tail (seventh in descent from Olioll Olum: see Connello), the ancestor of the Dalcassians of Thomond: Dealbhna, i.e. Dealbhaeth’s descendants. None of these have perpetuated their name except one, viz., Dealbhna mor, or the great Dealbhna, from whom the barony of Devlin in Westmeath received its name.

Dernish, Derinch, Derinish; oak island (dair).

Derrada, Derradd; Doire-fhada, long oak grove.

Derragh; the same as Darragh.

Derreen; little derry or oak grove or wood.

Derreens, Derries; oak groves.

Derry; Doire [Derry], an oak grove or wood.

Derryad, Derryadda; Doire-fhada, long oak wood.

Derrybane, Derrybawn; whitish oak wood.

Derrybeg; little oak wood.

Derrycreevy; the oak wood of the branchy tree.

Derrydorragh, Derrydorraghy; dark oak wood (dorcha)

Derryduff; black oak wood.

Derryfadda; long oak wood.

Derrygarriff, Derrygarve; rough oak wood (garbh).

Derrylahan, Derrylane; broad oak wood (leathan).

Derrylea; grey oak wood.

Derrylough, Derryloughan; the oak wood of the lake.

Derrymore; great oak wood.

Derrynahinch; the oak wood of the island or river meadow (inis).

Derrynane in Kerry; Doire-Fhionain [Derry-Eenane: Fh silent], the oak grove of St. Finan Cam, a native of Corkaguiny, who flourished in the sixth century.

Derrynaseer; the oak grove of the saers or carpenters.

Derryvullan in Fermanagh; Doire-Maelain [Derry-Velan: M aspirated], F.M., Maelan’s oak grove.

Desert, Disert, a desert or hermitage.

Desertcreat; corrupted from Disert-da-Chrioch [Di­sert-á-cree], F.M., the hermitage of the two territories.

Desertegny; Egnagh’s hermitage.

Desertmartin; Martin’s hermitage.

Desertmore; great desert or hermitage.

Desertserges in Cork; Saerghus’s hermitage.

Devenish Island in Lough Erne; Daimhinis [Davinish] F. M., the island of the oxen (damh).

Diamor; written in the Dinnseanchus, Diamar, i. e., a solitude.

Dingle; from Dingin, another form of Daingean, a fortress, by a change of n to l. Called in the annals, Daingean-ui-Chuis, now usually written Dingle-I-Coush, the fortress of O’Cush, the ancient proprietor.

Dinish, Deenish; Duibh inis [Divinish], black island.

Disert; the same as Desert.

Donabate; Domhnach-a’-bhaid, the church of the boat.

Donagh; Damhnach [Downagh], a church.

Donaghcloney in Down; the church of the cluain or meadow.

Donaghcumper in Kildare; the church of the cummer or confluence.

Donaghedy in Tyrone; Domhnach-Chaeide [Donaheedy] the church of St. Caidoc, a companion of St. Columbanus.

Donaghmore; great church.

Donaghmoyne in Monaghan; Domhnach-Mhaighin, the church of the little plain.

Donard; high dun or fort.

Donegal. The Danes had a settlement there before the Anglo-Norman invasion; and hence it was called Dun-na-nGall [Doonagall], the fortress of the Galls or foreigners.

Doneraile in Cork; written in the Book of Lismore Dun-air-aill, the fortress on the cliff.

Donnybrook; Domhnach-Broc, St. Broc’s church.

Donnycarney; Cearnach’s or Carney’s church.

Donohill; the fortress of the yew wood (eóchaill).

Donore; Dun-uabhair [Dunoor], F.M. the fort of pride.

Doogary; Dubhdhoire [Dooary], black derry or oak wood.

Doon; Dún, a fortress.

Doonan, Doonane; little dun or fort.

Doonard; high fort.

Doonass near Killaloe; Dun-easa, the fortress of the cataract, i.e. the great rapid on the Shannon.

Doonbeg; little fortress.

Doondonnell; Donall’s fortress.

Dooneen; little fort.

Doonfeeny; the fort of Finna (a woman).

Doonisky, Dunisky; the fort of the water (uisge).

Doonooney; Una’s fort.

Douglas; Dubh-ghlaise, black stream.

Down; a form of Dun, a fortress.

Downings; Dooneens or little forts.

Downpatrick takes its name from the large entrenched dun near the cathedral. In the first century this fortress was the residence of a warrior of the Red Branch Knights, called Celtchair, or Keltar of the battles, from whom it is called in Irish authorities, Dunkeltar. By ecclesiastical writers it is commonly called Dun-da-leth-glas, the fortress of the two broken locks (glas) or fetters. This long name was afterwards shortened to Dun or Down, which was extended to the county. The name of St. Patrick was added, to commemorate his connection with the place.

Downs; duns or forts.

Dreen; Draeighean [dreean], the blackthorn.

Dreenagh; a place producing blackthorns.

Dreenan; blackthorn, a place of blackthorns.

Drehidtarsna in Limerick; cross bridge.

Dressoge, Dressogagh; a briery or bushy place.

Dresternagh, Dresternan, Dristernan; same as Dressoge.

Drim; a form of druim, a ridge.

Drimeen, Drimmeen; little ridge.

Drirnna, Drimnagh; ridges, a place full of ridges or hills.

Drinagh, Drinaghan; a place producing dreens or black-thorns.

Drinan, Drinaun; the same as Dreenan.

Drishaghaun, Drishane, Drishoge; same as Dressoge.

Droghed; Droichead, a bridge.

Drogheda; Droiched-atha [Drohedaha], F.M., the bridge of the ford; from the ford across the Boyne, used before the erection of a bridge.

Drom; Druim, a ridge or long hill.

Dromada, Dromadda; long drum or ridge.

Drombeg, Drumbeg; small ridge.

Dromcolliher in Limerick; a corruption of Druim-Coll-choille [Drum-Collohill], the ridge of the hazel wood.

Dromdaleague in Cork; the ridge of the two liags or pillar stones.

Dromgarriff; rough ridge.

Dromin; same meaning as Drom.

Dromineer in Tipperary; Druim-inbhir [Druminver] the ridge of the inver or river mouth: because it is situated near where the Nenagh river enters Lough Derg.

Dromkeen; beautiful ridge.

Dromore; great ridge or long hill.

Dromtrasna; cross ridge.

Drum; Druim, a ridge or long hill.

Drumad; Druim-fhada, long ridge.

Dromadoon; the ridge of the dun or fort.

Drumahaire in Leitrim; Druim-da-ethiar [Drum-a-ehir], F.M., the ridge of the two air-demons.

Drumanure; the ridge of the yew tree.

Drumany, Drummany; ridges, ridged land.

Drumard; high ridge or long hill.

Drumatemple; the ridge of the temple or church.

Drumavaddy; the ridge of the dog (madadh).

Drumballyroney; the ridge of O’Roney’s town.

Drumbane, Drumbaun; white ridge.

Drumbarnet, the ridge of the gap (bearna).

Drumbo, Drumboe; Druimbo, F.M., the cow’s ridge.

Drumbrughas; the ridge of the farm-house.

Drumcanon; the ridge of the white-faced cow: ceann­fhionn [canon], whitehead.

Drumcar in Louth; Druim-caradh [Drumcara], F.M., the ridge of the weir.

Drumcliff in Sligo; Drium-chliabh [Drumcleev], F.M., the ridge of the baskets.

Drumcolumb; St. Columba’s ridge.

Drumcondra; Conra’s ridge.

Drumcrin; the ridge of the tree (crann).

Drumcrow; the ridge of the cattle sheds (cro).

Drumcullen, Drumcullion; the ridge of holly.

Drumderg; Druim-dearg, red ridge.

Drumduff; Druim-dubh, black ridge.

Drumfad; Druim-fada, long ridge.

Drumgill; the ridge of the Gall or foreigner.

Drumgoose, Drumgose; the ridge of the caves (cuas).

Drumgowna, Drumgownagh; Druirn-gamhnach, the ridge of the heifers.

Drumharriff, Drumherriff; Druim-thairbh [Drum-harriv], the ridge of the bull.

Drurnhillagh in Cavan and Monaghan; Druim-shaileach, the ridge of the sallows, same as Drumsillagh in other counties, in which the original s sound is retained.

Drurnhirk; Druim-thuirc, the ridge of the boar.

Drumhome in Donegal. In O’C. Cal. the name is written Druim-Thuama [Drumhooma], and Adamnan translates it Dorsum Tommae, the ridge of Tomma, a pagan woman’s name.

Drumillard, Drummillar; the eagle’s ridge (iolar).

Drumkeen; beautiful ridge.

Drumkeeran; the ridge of the quicken trees.

Drumlane; Druim-leathan [lahan], F.M., broad ridge.

Drumlease; Druim-lias, the ridge of the huts.

Drumlish; the ridge of the lis or fort.

Drumlougher; the ridge of the rushes (luachra).

Drumman; same meaning as Drum.

Drummeen; little ridge.

Drummin; same meaning as Drum.

Drummond; a corrupt form of Drumman.

Drummuck; the ridge of the pigs (rnuc).

Drummully; the ridge of the summit (mullach).

Drumnacross; the ridge of the cross.

Drumneen; little ridge.

Drumquin; Druim-Chuinn, Conn’s ridge.

Drumraine, Drumrainy; ferny ridge (ráthain).

Drumreagh; Druim-riabhach, grey ridge.

Drumroe; Druim-ruadh, red ridge.

Drumroosk; the ridge of the roosk or marsh.

Drumshallon; the ridge of the gallows (sealan).

Drumshanbo; the ridge of the old both or tent (sean, old).

Drumsillagh; see Drumhillagh.

Drumnsna, Drumsnauv; Druim-snamha [snawa], the ridge of the swimming. See Lixnaw.

Drumsurn; the ridge of the furnace or kiln (sorn).

Duagh in Kerry; Dubh-ath [Dooah], black ford, from a ford on the river Feale.

Dublin. The name is written in the annals Duibh-linn [Duvlin], which, in some of the Latin Lives of the saints, is translated Nigra therma, black pool; it was originally the name of that part of the Liffey on which the city is built, and is sufficiently descriptive at the present day. In very early ages an artificial ford of hurdles was constructed across the Liffey, where the main road from Tara to Wicklow crossed the river; and the city that subsequently sprung up around it was called from this circumstance Ath-cliath [Ah-clee], F.M., the ford of hurdles, which was the ancient name of Dublin. This name is still used by speakers of Irish in every part of Ireland; but they join it to Bally—Baile-atha-cliath (which they pronounce Blaa-clee), the town of the hurdle ford.

Dufferin, barony of, in Down; Dubh-thrian [Duv-reen], F.M., the black treen or third part.

Duhallow in Cork; Duthaigh-Ealla [Doohy-alla], F. M., the district of the Allo, from the Blackwater river, a portion of which was anciently called the Allo.

Dulane in Meath; Tuilen, F.M., little tulach or hill.

Duleek in Meath; Daimhliag [Davleeg], O’C.Cal., stone house or church (daimh, a house, and liag).

Dunamase in Queen’s County; should have been called Dunmask, for the Irish name is Dun-Masg, F.M., the fortress of Masg, who was one of the ancestors of the Leinster people.

Dunamon in Galway; so called from a castle of the same name on the Suck; but the name, which the annalists write Dun-Iomgain, Imgan’s fort, was anciently applied to a dun, which is still partly preserved.

Dunboe in Derry; the fortress of the cow.

Dunboyne; Dun-Baeithin, Baeithin’s or Boyne’s fort.

Duncannon; Conan’s fortress.

Duncormick; Cormac’s fortress.

Dundalk. The name was originally applied to the great fortress now called the moat of Castletown, a mile inland, which was the residence of Cuchullin, chief of the Red Branch knights in the first century. Dun-Dealgan [Dalgan], F.M., the fortress of Delga, a Firbolg chief, who built it.

Dunderrow in Cork; written Dun-dermaigi [Dundarwah] in the Book of Leinster, the fortress of the oak-plain (see Durrow); and the large dun from which it received the name is still in existence, half a mile south of the village.

Dundonald in Down, Donall’s fortress; so called from a fort that stands not far from the church.

Dundrum; Dun-droma, F.M., the fortress on the ridge or hill.

Duneane in Antrim; written in the Felire of Aengus, Dun-da-én [Dan-ā-ain], the fortress of the two birds.

Dunfanaghy; Dun-Fionnchon [Finahan], Finchu’s fort.

Dungannon in Tyrone; Dun-Geanainn [Gannin], F.M., Geanan’s or Gannon’s fortress.

Dungarvan; Dun-Garbhain, F.M., Garvan’s fortress.

Dunhill; Dun-aille, the fortress of the cliff.

Dunkineely in Donegal; Dun-mhic-Chionnfhaelaidh [Dunvickaneely], Mackineely’s fort.

Dunkit; Ceat’s or Keth’s fortress.

Dunleer in Louth. Old name Land-léri (Book of Leinster), the church (land or lann) of austerity. Present name formed by substituting dun a fort for lann.

Dunluce castle near the Giant’s Causeway;  Dunlios, F.M., strong lios or fort. Dun is here an adjective, meaning strong.

Dunmanaway in Cork. Old name Dun-na-mbeann [Dun­aman], F.M., the fortress of the gables or pinnacles. The last syllable way is from buidhe yellow [bwee or with the b aspirated, wee]:- Dunmanway, the fortress of the yellow pinnacles.

Dunrnore; great fort.

Dunmurry; Dun-Mhuireadhaigh, Murray’s fort.

Dunquin in Kerry; Dun-caein [Dunkeen], F.M., beautiful fort.

Dunshaughlin in Meath. A church was founded here for bishop Sechnall or Secundinus, St. Patrick’s nephew; and hence it was called Domhnach-Seachnaill [Donna-Shaughnill], F.M., the church of St. Sechnall, which has been shortened to the present name.

Duntryleague in Limerick. According to a passage in the Book of Lismore, a dun or palace was built here for Cormac Cas, son of Olioll Olum (see Connello); and his bed was supported by three liagáns or pillar stones, from which the place was called Dun-tri-liagh, the fortress of the three liaghs or pillar stones.

Durrow in King’s County, a favourite residence of St. Columbkille. Venerable Bede has a short passage in his Eccl. Hist. (lib. iii., cap. iv.), in which the ori­ginal form and translation of this name are given:- ‘‘Before he (Columba) passed over into Britain, he had built a noble monastery in Ireland, which, from the great number of oaks, is in the Scotic (Irish) language called Dearmhagh [Darwah], the field of the oaks” (dair and magh).

Dysart and Dysert; the same as Desert.

Dysartenos in Queen’s County. St. Aengus the Culdee, who died in the year 824, built a cell for himself here; and hence the place was called Disert-Aenghusa, Aengus’s hermitage.