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Incidence in Irish (Ionsaitheacht): Meaning, Pronunciation, Usage

The Irish for incidence is ionsaitheacht, a feminine noun.
Updated October 2026Report a mistake

How to say “incidence” in Irish

Irish:
ionsaitheacht
English:
incidence
Word type:
noun
Gender:
feminine
Pronunciation:
“IN-see-hukht”  /ˈɪnˠsˠiːhəxt̪ˠ/
Various forms
Genitive singular:
ionsaitheachta, na hionsaitheachta (e.g. uillinn ionsaitheachta, angle of incidence)

What does “ionsaitheacht” mean?

incidence
In physics, the way a ray of light or other radiation falls on or strikes a surface, as in the angle of incidence.Also: angle of incidence, point of incidence.

“Ionsaitheacht” with the article

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

an ionsaitheacht
the incidence
No change: feminine nouns starting with a vowel keep their form after an

“Ionsaitheacht” in a sentence: Irish examples

Common Irish sentences using ionsaitheacht, the Irish word for incidence.

Tomhais uillinn na hionsaitheachta leis an uillinntomhas.
Measure the angle of incidence with the protractor.
Is ionann uillinn ionsaitheachta agus uillinn fhrithchaithimh.
The angle of incidence equals the angle of reflection.
Tá an ionsaitheacht ag brath ar uillinn an tsolais.
The incidence depends on the angle of the light.
Athraíonn ionsaitheacht ghathanna na gréine de réir an tséasúir.
The incidence of the sun's rays changes with the season.
Rinneamar staidéar ar ionsaitheacht ghathanna na gréine.
We studied the incidence of the sun's rays.
Léiríonn an léaráid pointe na hionsaitheachta.
The diagram shows the point of incidence.
Míníonn an múinteoir ionsaitheacht sa rang fisice.
The teacher explains incidence in the physics class.

Other nouns in Irish

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Incidence in Irish: frequently asked questions

What is the Irish for incidence?

The Irish for incidence is ionsaitheacht (pronounced “IN-see-hukht”). It’s a feminine noun.

How do you pronounce ionsaitheacht in Irish?

Ionsaitheacht is said like “IN-see-hukht” (IPA /ˈɪnˠsˠiːhəxt̪ˠ/).

Does ionsaitheacht have a plural?

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

Why does ionsaitheacht sometimes have a t or h in front of it?

Irish nouns beginning with a vowel take a prefix after certain words: an ionsaitheacht (the incidence), a hionsaitheacht (her incidence), a n-ionsaitheacht (their incidence).

Is 'ionsaitheacht' the same as 'ionsaí' (attack)?

They share a root, but 'ionsaitheacht' is a technical term for incidence, as in 'uillinn ionsaitheachta', while 'ionsaí' means an attack or assault.

Can I use 'ionsaitheacht' for the incidence of a disease?

It is best kept for the physics sense, as in 'uillinn ionsaitheachta'. For how often something happens, such as a disease, use a word like 'minicíocht' (frequency).

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