About this phrase
Oifig is a feminine noun that means office.
An is the singular definite article, the.
Post is a masculine noun that means post (in the sence of both 'mail' and 'job'). It is in the genitive case here because it is the second noun in a two-noun cluster. Being in the genitive causes the ending to be slenderised (—oist). The presence of the definite article in the construction causes the begining to be lenited (pho—)
Thus, oifig an phoist: the post office (literally, 'the office of the post').
Similarly, fear an phoist / bean an phoist: the postman / the postwoman.
Notes (important ones)
- In Irish, where two-noun clusters feature the definite article, it does not generally occur at the start of the cluster:
- Oifig an phoist is correct.
- But an oifig poist is wrong.
- In the same way, bean an leanna is correct.
- And an bhean leanna is wrong.
- This is not a universal rule however; there are subtleties:
- Bean an tí: the woman of the house (that is, the wife of the house, or the woman who owns the house outright).
- An bhean tí: the housekeeper (literally, 'the housewoman').
Further study is encouraged.
- Also, the definite article only occurs once in the cluster whereas it may appear twice in English ('the office of the ombudsman', 'the rights of the people' and so on):
- Therefore, an oifig an phoist would be quite wrong.
- In naturalistic speech — even in more formal registers — this phrase is generally pronounced oifig a' phoist. Similarly:
- Fear a' phoist.
- Bean a' phoist.
- Bean a' leanna.
- Bean a' tí.
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