Simple Prepositions in Irish

In Brief

Irish simple prepositions are short words such as ag “at,” ar “on,” i “in,” le “with,” and ó “from.” They come before a noun, but the noun’s first sound may change: compare teach “house,” i dteach “in a house,” and ó theach “from a house.” Learn each preposition together with a useful phrase rather than relying on a one-word English equivalent.

Overview

A preposition is a linking word that shows a relationship such as place, direction, time, source, or accompaniment. In le Máire (“with Máire”), for example, le links the action or situation to Máire. The Irish term is réamhfhocal, literally a word placed before another word.

Simple prepositions appear in Irish from A1 onward. You need them to say where somebody is, where something comes from, whom you are with, and what a conversation is about. They also occur in many everyday expressions whose wording differs from English. Irish can express possession as “a book is at me,” for instance, using ag; that larger pattern is covered under prepositional pronouns.

The main beginner challenge is not the position of the preposition—it normally comes before its complement (the noun or phrase that completes its meaning)—but what follows it. Some prepositions cause an initial mutation, a regular change to the first consonant. The two mutations most relevant here are lenition (séimhiú, usually written by adding h) and eclipsis (urú, in which another consonant is written before the original one). English does not change the beginning of “house” after “in” or “from,” so these forms need deliberate practice.

How It Works

The core set

Irish	Core meaning	Typical use
ag	at	location at a person/place; an activity in progress
ar	on	position on a surface; states and many fixed expressions
as	out of, from	movement from inside; origin or material in some expressions
de	of, off, from	separation, source, or relation
do	to, for	recipient, destination, or benefit
faoi	under, about	physical position; subject matter
i	in, into	location inside or movement inside
le	with, by	accompaniment, instrument, possession, or authorship
ó	from, since	starting point in place or time
roimh	before, in front of	earlier than; ahead of
thar	over, across, past	movement or position beyond something
trí	through, by means of	passage through; means or cause

These translations are starting points, not equations. English “at” may be ag, i, or part of a completely different Irish construction. Conversely, ar covers not only literal “on” but expressions such as ar scoil (“at school”) and ar maidin (“in the morning”).

Preposition + noun

The basic order is straightforward:

preposition + noun or noun phrase

• le Máire — with Máire
• faoi Ghaeilge — about Irish
• roimh an gcruinniú — before the meeting

There is no separate indefinite article corresponding to English “a/an.” Thus i dteach can mean “in a house,” while context supplies the indefiniteness.

Mutations after simple prepositions

Before a noun without the definite article, i regularly causes eclipsis:

Base word	After i	Meaning
baile	i mbaile	in a town
teach	i dteach	in a house
Corcaigh	i gCorcaigh	in Cork
páirc	i bpáirc	in a park
farraige	i bhfarraige	in a sea / at sea

With a vowel, i is normally written in: in Éirinn (“in Ireland”), in oifig (“in an office”). Do not treat in as an unrelated word; it is the form used before vowels.

Several common simple prepositions normally lenite a following consonant when there is no article: de, do, faoi, ó, roimh, and trí. Lenition gives forms such as faoi bhord (“under a table”), ó theach (“from a house”), and trí pháirc (“through a park”). Ar also appears with lenition in many ordinary phrases, but its mutation patterns include established expressions that must be learned as units. Compare ar bhord (“on board”) with ar bord in some conventional uses, and learn frequent phrases such as ar scoil without trying to rebuild them from an English rule.

Not every consonant displays lenition in writing. A vowel cannot be lenited, and l, n, and r do not take an added h. Ag, as, and le do not normally mutate a following bare noun: ag doras (“at a door”), as bosca (“out of a box”), le cara (“with a friend”). Proper names may behave differently according to the preposition and the name: le Máire, but ó Bhaile Átha Cliath.

With the definite article

English “the” is represented by forms of an or na, but a preposition plus the article may contract or trigger a different mutation. Important forms include sa/san from i + an, den from de + an, don from do + an, and ón from ó + an:

• sa teach — in the house
• san oifig — in the office
• don fhear — to the man
• ón siopa — from the shop
• ar an mbord — on the table
• leis an mbean — with the woman

For now, recognize these as complete chunks. The interaction of gender, number, dialect, and mutation belongs to the later topic Prepositions with the Article.

Place, direction, and time

A preposition’s translation depends on the relationship intended:

• Tá an cupán ar an mbord. — The cup is on the table. (position)
• Chuir mé an cupán ar an mbord. — I put the cup on the table. (destination)
• Tháinig sí ó Ghaillimh. — She came from Galway. (source)
• Fan anseo go dtí tar éis lóin. — Stay here until after lunch. (time relationship)

Irish does not always make the same “at/in/on” choices as English. Memorize ar maidin (“in the morning”), san oíche (“at night”), and ag an deireadh seachtaine (“at the weekend”) as Irish phrases.

Examples in Context

Irish	English	Note
Tá an leabhar ar an mbord.	The book is on the table.	ar + definite noun
Tá siad i dteach mór faoin tuath.	They are in a large house in the countryside.	i eclipses teach
Chuaigh mé le Máire go dtí an siopa.	I went with Máire to the shop.	accompaniment
Tháinig an bus ó Bhaile Átha Cliath.	The bus came from Dublin.	source or starting point
Tá Seán ag an doras.	Seán is at the door.	location at a point
Thóg sí an litir as an mála.	She took the letter out of the bag.	movement from inside
Thit an hata den chathaoir.	The hat fell off the chair.	separation from a surface
Thug mé an eochair do Nóra.	I gave the key to Nóra.	recipient; do lenites the name
Tá an cat faoin mbord.	The cat is under the table.	faoi + an contracts to faoin
Bhíomar ag caint faoin scannán.	We were talking about the film.	faoi marks the topic
Scríobh sé an nóta le peann.	He wrote the note with a pen.	instrument or means
Fan anseo roimh an rang.	Wait here before the class.	earlier in time
Shiúil siad thar an droichead.	They walked across the bridge.	movement across
Chuaigh an traein trí thollán fada.	The train went through a long tunnel.	trí lenites tollán
Tá sí ar scoil anois.	She is at school now.	fixed everyday phrase

Common Mistakes

Translating English “in” without applying eclipsis

• Wrong: i teach
• Right: i dteach
• Why: Before a bare consonant-initial noun, i normally causes eclipsis. Learn teach → i dteach as a model.

Using i an for “in the”

• Wrong: i an teach
• Right: sa teach
• Why: i + an normally contracts to sa before a consonant and san before a vowel: san oifig.

Assuming one English preposition always has one Irish match

• Wrong: i an mbord for “on the table”
• Right: ar an mbord
• Why: English “in,” “on,” and “at” divide up space differently from Irish i, ar, and ag. Choose the Irish relationship, not an automatically translated word.

Forgetting lenition after a preposition

• Wrong: ó teach, trí páirc
• Right: ó theach, trí pháirc
• Why: ó and trí normally lenite a following bare noun. The written h represents a changed sound, not an optional spelling decoration.

Treating motion and source as the same relationship

• Wrong: Tá sí ag teacht i Gaillimh when you mean “She is coming from Galway.”
• Right: Tá sí ag teacht ó Ghaillimh.
• Why: i locates something inside a place; ó marks its origin or starting point.

Keeping a separate pronoun after the preposition

• Wrong: le mé for “with me”
• Right: liom
• Why: Irish prepositions usually combine with personal pronouns into one word. This is a separate but essential system: le + mé → liom, ag + mé → agam, ar + mé → orm.

Usage Notes

Many of the most frequent Irish prepositional phrases are idiomatic. Tá carr agam literally has the shape “a car is at me” but means “I have a car.” Is maith liom caife literally relates coffee as “good with me” and means “I like coffee.” Their English translations are useful for meaning, but the Irish structure is the one to remember.

Mutation and article forms vary somewhat across dialects, especially in speech. You may hear or read forms that differ from a course’s preferred standard. At beginner level, use the standard form taught by your materials consistently, while learning to recognize alternatives rather than labeling every unfamiliar form a mistake.

Prepositions also form part of phrasal expressions. In ag obair (“working,” literally “at work”), ag introduces a verbal noun—the noun-like form used for an activity. In ar fáil (“available”) and faoi dheireadh (“finally”), translating each word separately gives little help. A phrase notebook is therefore more useful than a list containing only ar = on and faoi = under.

Beyond the Basics / Advanced Use

You do not need to master all of this at A1, but these short words lead into several major parts of Irish grammar.

First, almost every simple preposition has a set of prepositional pronouns, forms combining the preposition with “me,” “you,” “him,” and so on. For example, ag gives agam (“at me”), agat (“at you”), and aige/aici (“at him/her”); le gives liom, leat, leis, léi. These are not contractions invented in casual speech: they are the normal grammatical forms.

Second, the definite article creates a fuller mutation system. Number and grammatical gender (the noun class conventionally called masculine or feminine) can affect what follows. Standard written Irish and the major dialects do not agree in every detail, so advanced learners should compare forms in real texts and recordings with the variety they are studying.

Third, preposition choice is controlled by particular verbs and adjectives. English might use a direct object where Irish uses a preposition, or vice versa. Éist le means “listen to,” fan le means “wait for,” and smaoinigh ar means “think about.” Learn the governing preposition as part of the expression: not just éist, but éist le.

Finally, Irish has compound prepositions—multiword units such as ar feadh (“for the duration of”), i ndiaidh (“after”), and os comhair (“in front of”). The noun after many of these takes the genitive, a form marking relationships often expressed by English “of.” That system is best approached after the simple prepositions are secure.

Practice Tips

1. Build phrase families. Start with one noun and move it through useful relationships: i dteach, ó theach, faoi theach, le teach. Say the forms aloud so that mutation becomes a sound pattern, not merely an added letter.
2. Record whole chunks, not equations. Put ar scoil, ar maidin, ag an doras, and faoin mbord on flashcards with a short sentence. Avoid cards that only say “ar = on.”
3. Describe a real room or journey. Say where five objects are and trace a route using i, ar, faoi, ó, thar, and trí. Then check both your choice of preposition and the beginning of the following noun.

Related Concepts

• Prerequisite: Lenition (Séimhiú) — explains the consonant change seen in forms such as ó theach and trí pháirc.
• Next step: Prepositional Pronouns — learn forms such as agam, orm, and liom.
• Next step: Location and Directions — use prepositions to locate places and give routes.
• Next step: Prepositions with the Article — study sa, san, den, don, ón and their mutations in detail.
• Later reference: Compound Prepositions — extend the system to expressions such as ar feadh and os comhair.