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Mystery in Irish (Rúndiamhair): Meaning, Pronunciation, Usage

‘rúndiamhair’ also means: religious mystery

The Irish for mystery is rúndiamhair, a feminine noun (plural rúndiamhra).
Updated October 2026Report a mistake

How to say “mystery” in Irish

Irish:
rúndiamhair
English:
mystery, religious mystery
Word type:
noun
Gender:
feminine
Pronunciation:
“ROON-dee-uh-vir”  /ˈɾˠuːnˌdʲiəwəɾʲ/
Various forms
Plural:
rúndiamhra (mysteries)
Genitive singular:
rúndiamhaire, na rúndiamhaire (e.g. réiteach na rúndiamhaire, the solution of the mystery)
Genitive plural:
rúndiamhra, na rúndiamhra (e.g. leabhar na rúndiamhra, the book of the mysteries)

What does “rúndiamhair” mean?

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

mystery
Something secret or hidden that cannot easily be understood or explained.Also: enigma, secret, hidden thing.
1 other meaning: religious mystery
2religious mystery
A truth of religious faith that is beyond human understanding, such as a mystery of the rosary.Also: mystery of faith, mystery of the rosary.

Other Irish words for mystery: rún (secret), mistéir (mystery)

“Rúndiamhair” with the article

The plural of mystery in Irish is rúndiamhra. Here is rúndiamhair after the article (an t-alt), in the singular and the plural.

an rúndiamhair
the mystery
No change after an
na rúndiamhra
the mysteries
Plural: no change after na

“Rúndiamhair” in a sentence: Irish examples

Common Irish sentences using rúndiamhair, the Irish word for mystery.

Is rúndiamhair í sin dom fós.
That is still a mystery to me.
Níor réitíodh an rúndiamhair riamh.
The mystery was never solved.
Ní raibh aon duine in ann bun na rúndiamhaire a fháil.
Nobody could get to the bottom of the mystery.
Tá rúndiamhra na beatha thar ár dtuiscint.
The mysteries of life are beyond our understanding.
Dúirt siad rúndiamhra na Coróineach Muire le chéile.
They said the mysteries of the rosary together.
Is rúndiamhair mhór í fós cad a tharla.
What happened is still a big mystery.
Is maith liom scéalta faoi rúndiamhra.
I like stories about mysteries.

Other nouns in Irish

More everyday Irish nouns to learn next.

Mystery in Irish: frequently asked questions

What is the Irish for mystery?

The Irish for mystery is rúndiamhair (pronounced “ROON-dee-uh-vir”). It’s a feminine noun and the plural is rúndiamhra. Depending on context it can also mean religious mystery.

How do you pronounce rúndiamhair in Irish?

Rúndiamhair is said like “ROON-dee-uh-vir” (IPA /ˈɾˠuːnˌdʲiəwəɾʲ/).

What is the plural of mystery in Irish?

The plural of rúndiamhair is rúndiamhra; with the article, na rúndiamhra means “the mysteries”. The genitive plural is rúndiamhra, as in leabhar na rúndiamhra (the book of the mysteries).

Does rúndiamhair have more than one meaning?

Yes. Rúndiamhair can mean mystery or religious mystery, depending on context; the first is the most common.

How is 'rúndiamhair' different from 'mistéir'?

Both mean mystery, but 'rúndiamhair' is the usual word, especially for religious mysteries, while 'mistéir' is used more for a puzzling event.

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