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Semicircle in Irish (Leathroth): Meaning, Pronunciation, Usage

The Irish for semicircle is leathroth, a masculine noun (plural leathrothaí).
Updated October 2026Report a mistake

How to say “semicircle” in Irish

Irish:
leathroth
English:
semicircle
Word type:
noun
Gender:
masculine
Pronunciation:
“LAH-roh”  /ˈl̠ʲahˌrˠɔ/
Various forms
Plural:
leathrothaí (semicircles)
Genitive singular:
leathrotha, an leathrotha (e.g. lár an leathrotha, the centre of the semicircle)
Genitive plural:
leathrothaí, na leathrothaí (e.g. líníocht na leathrothaí, the drawing of the semicircles)

What does “leathroth” mean?

semicircle
Half of a circle, a curved shape like the half of a wheel.Also: half circle, half-wheel.

“Leathroth” with the article

The plural of semicircle in Irish is leathrothaí. Here is leathroth after the article (an t-alt), in the singular and the plural.

an leathroth
the semicircle
No change after an
na leathrothaí
the semicircles
Plural: no change after na

“Leathroth” in a sentence: Irish examples

Common Irish sentences using leathroth, the Irish word for semicircle.

Tarraing leathroth ar an leathanach.
Draw a semicircle on the page.
Shuigh na páistí i leathroth timpeall an mhúinteora.
The children sat in a semicircle around the teacher.
Tá an leathroth seo róbheag.
This semicircle is too small.
Tomhais trastomhas an leathrotha.
Measure the diameter of the semicircle.
Rinne sé dhá leathroth le compás.
He made two semicircles with a compass.
Tá leathrothaí bána ar an bpáirc.
There are white semicircles on the pitch.
Seasaigí sa leathroth, le bhur dtoil.
Stand in the semicircle, please.

Other nouns in Irish

More everyday Irish nouns to learn next.

Semicircle in Irish: frequently asked questions

What is the Irish for semicircle?

The Irish for semicircle is leathroth (pronounced “LAH-roh”). It’s a masculine noun and the plural is leathrothaí.

How do you pronounce leathroth in Irish?

Leathroth is said like “LAH-roh” (IPA /ˈl̠ʲahˌrˠɔ/).

What is the plural of semicircle in Irish?

The plural of leathroth is leathrothaí; with the article, na leathrothaí means “the semicircles”. The genitive plural is leathrothaí, as in líníocht na leathrothaí (the drawing of the semicircles).

Is 'leathroth' the same as 'leathchiorcal'?

Both mean semicircle; 'leathchiorcal' is common in maths, while 'leathroth' literally means half-wheel and is also used for a semicircular shape or arrangement.

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