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Duality in Irish (Déachas): Meaning, Pronunciation, Usage

‘déachas’ also means: dualism

The Irish for duality is déachas, a masculine noun.
Updated October 2026Report a mistake

How to say “duality” in Irish

Irish:
déachas
English:
duality, dualism
Word type:
noun
Gender:
masculine
Pronunciation:
“DAY-uh-khus”  /ˈdʲeːəxəsˠ/
Various forms
Genitive singular:
déachais, an déachais (e.g. teoiric an déachais, the theory of duality)

What does “déachas” mean?

“Déachas” has two alternative meanings. The most common comes first.

duality
The state or quality of being twofold, consisting of two parts or elements.Also: twofoldness, doubleness.
1 other meaning: dualism
2dualism
A philosophical or religious doctrine that reality consists of two basic opposing principles, such as mind and matter or good and evil.Also: dualist doctrine.

“Déachas” with the article

Here is déachas after the article (an t-alt).

an déachas
the duality
No change after an

“Déachas” in a sentence: Irish examples

Common Irish sentences using déachas, the Irish word for duality.

Is coincheap tábhachtach san fhealsúnacht é an déachas.
Dualism is an important concept in philosophy.
Labhair an léachtóir faoi dhéachas Descartes.
The lecturer spoke about Descartes' dualism.
Tá déachas le feiceáil sa scéal seo.
A duality can be seen in this story.
Ní ghlacann sí le déachas an choirp agus an anama.
She does not accept the dualism of body and soul.
Scríobh sé aiste ar stair an déachais.
He wrote an essay on the history of dualism.
Bíonn déachas idir an mhaith agus an t-olc i go leor creideamh.
Many religions have a dualism between good and evil.
Is léir an déachas i gcarachtar an laoich.
The duality in the hero's character is clear.

Other nouns in Irish

More everyday Irish nouns to learn next.

Duality in Irish: frequently asked questions

What is the Irish for duality?

The Irish for duality is déachas (pronounced “DAY-uh-khus”). It’s a masculine noun. Depending on context it can also mean dualism.

How do you pronounce déachas in Irish?

Déachas is said like “DAY-uh-khus” (IPA /ˈdʲeːəxəsˠ/).

Does déachas have a plural?

No plural form is given for déachas in the standard. Many abstract and mass nouns in Irish have no plural.

Does déachas have more than one meaning?

Yes. Déachas can mean duality or dualism, depending on context; the first is the most common.

Why does déachas change to dhéachas or ndéachas?

Irish changes the start of some words after certain words. After mo (my) déachas becomes mo dhéachas (lenition), and after ár (our) or i (in) it becomes ár ndéachas (eclipsis).

Is 'déachas' the same as 'déacht'?

No. 'Déachas' means duality or dualism, while 'déacht' means deity or divinity, from 'dia'.

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