HeyRua Get the app

Dangerous in Irish (guasach): Meaning, Forms, Examples

The Irish for dangerous is guasach: bóthar guasach, a dangerous road.
Updated October 2026Report a mistake

How to say “dangerous” in Irish

Irish:
guasach
English:
dangerous
Word type:
adjective
More dangerous:
níos guasaí
Most dangerous:
is guasaí
Plural:
guasacha
Pronunciation:
“GOO-us-ukh”  /ˈɡuəsˠəx/

What does “guasach” mean?

dangerous
Likely to cause harm, injury or loss; full of danger.Also: perilous, hazardous, risky, unsafe.

Other Irish adjectives for dangerous: contúirteach (dangerous), baolach (dangerous), dainséarach (dangerous)

“Guasach” after a noun

An Irish adjective comes after its noun. Here is guasach after bóthar (road, masculine), after aill (cliff, feminine) and after a plural.

after a masculine nounbóthar guasacha dangerous road
after a feminine nounaill ghuasacha dangerous cliff
after a plural nounbóithre guasachadangerous roads

séimhiú (the h) the ending

feminine
aillcliff
+
guasachdangerous
=
aill ghuasacha dangerous cliff

After a feminine noun the adjective gets a séimhiú, an h after its first letter: aill ghuasach. After a masculine noun it stays as it is: bóthar guasach.

plural
bóithreroads
+
guasachadangerous, plural
=
bóithre guasachadangerous roads

With a plural noun the adjective takes its plural form, guasacha. It also gets an h after a plural that ends in a slender consonant; after other plurals it does not: aillte guasacha.

More dangerous, most dangerous, very dangerous

níosmore
+
guasaídangerous
=
níos guasaímore dangerous
ismost
+
guasaídangerous
=
is guasaímost dangerous

Tá an fharraige níos guasaí inniu ná inné. The sea is more dangerous today than yesterday.

more dangerousníos guasaíin the past tense: ní ba ghuasaí
most dangerousis guasaíin the past tense: ba ghuasaí
as dangerous aschomh guasach leno change after chomh
very dangerousan-ghuasachan- lenites, except d, t and s
too dangerousróghuasachró- lenites

“Guasach” in a sentence: Irish examples

With a masculine noun, a feminine noun, a plural, a comparison and on its own.

Is bóthar guasach é sa gheimhreadh.
It is a dangerous road in winter.
Shiúil siad ar aill ghuasach cois farraige.
They walked on a dangerous cliff by the sea.
Is obair ghuasach í sin.
That is dangerous work.
Tá an fharraige níos guasaí inniu ná inné.
The sea is more dangerous today than yesterday.
Tá sé guasach snámh anseo.
It is dangerous to swim here.

Other adjectives in Irish

More everyday Irish adjectives to learn next.

Dangerous in Irish: frequently asked questions

What is the Irish for dangerous?

The Irish for dangerous is guasach (pronounced “GOO-us-ukh”). It comes after the noun: bóthar guasach, a dangerous road; aill ghuasach, a dangerous cliff.

How do you say more dangerous and most dangerous in Irish?

níos guasaí is more dangerous and is guasaí is most dangerous. In the past tense they become ní ba ghuasaí and ba ghuasaí.

Why does guasach become ghuasach?

After a feminine singular noun an adjective is lenited: it gets an h after its first letter. So aill ghuasach (a dangerous cliff) but bóthar guasach (a dangerous road), because bóthar is masculine.

What is the plural of guasach?

With a plural noun guasach becomes guasacha: bóithre guasacha, aillte guasacha.

How do you say very dangerous in Irish?

an-ghuasach. Too dangerous is róghuasach, and as dangerous as is chomh guasach le.

What is the difference between 'guasach' and 'contúirteach'?

Both mean dangerous; 'contúirteach' is the most common everyday word, while 'guasach' is slightly more formal and is often used in official terms such as 'ábhar guasach' (hazardous material).

Learn Irish by
actually speaking it

Learn everyday Irish words like guasach through guided conversation with Rua.

7-day free trial. Cancel anytime.

The HeyRua app home screen