déag

See also: deag

Irish edit

From Middle Irish déc, from Old Irish deec, deac, from Proto-Celtic *dekam -kʷe (literally “and ten”), with loss of the first k by dissimilation.^[1] Cognate with Scottish Gaelic deug and Manx jeig.

déag

Does not function as a suffix; functions as an entirely separate word. Follows the first part of the numeral as well as the noun (if any). Lenites in disjunctive numbers after dó (“two”) and in attributive numerals when the item counted is in the singular and ends in a vowel or is in the plural and ends in a slender consonant (except cinn):

‎ocht (“eight”) + ‎déag → ‎ocht déag (“eighteen”)

aon bhuachaill déag ― eleven boys

trí cinn déag ― thirteen (items)

ceithre úll déag ― fourteen apples

cúigear déag ― fifteen (people)

sé bhád déag ― sixteen boats

seacht dteach déag ― seventeen houses

naoi mbliana déag ― nineteen years

But:

‎dó (“two”) + ‎déag → ‎dó dhéag (“twelve”)

dhá ghiota dhéag ― twelve pieces

trí mhadra dhéag ― thirteen dogs

ceithre méadair dhéag ― fourteen metres

Additionally, never lenites in ordinal numbers:

an t-aonú lá déag ― the eleventh day

an ceathrú duine déag ― the fourteenth person

an tseachtú mí déag ― the seventeenth month

Irish mutation
Radical	Lenition	Eclipsis
déag	dhéag	ndéag
Note: Some of these forms may be hypothetical. Not every possible mutated form of every word actually occurs.

^ Schrijver, Peter (1993), “Varia IV. OIr. dëec, dëac”, in Ériu, volume 44, pages 181–84

“déag”, in Historical Irish Corpus, 1600–1926, Royal Irish Academy
G. Toner, M. Ní Mhaonaigh, S. Arbuthnot, D. Wodtko, M.-L. Theuerkauf, editors (2019), “deec”, in eDIL: Electronic Dictionary of the Irish Language
Finck, F. N. (1899) Die araner mundart (in German), volume II, Marburg: Elwert’sche Verlagsbuchhandlung, page 80
Ó Dónaill, Niall (1977), “déag”, in Foclóir Gaeilge–Béarla, Dublin: An Gúm, →ISBN