Learn Hardcore Icelandic: Brúðkaupsdagurinn er sérstakur dagur.

brúðkaup – a neuter noun meaning wedding
brúðkaups – the genitive singular of brúðkaup, meaning of a wedding
dagur – a masculine noun meaning day
dagurinn – dagur
- the definite ending -inn, meaning the day
brúðkaupsdagur – wedding-day, literally day of a wedding
brúðkaupsdagurinn – the wedding day

So brúðkaupsdagurinn literally means the day of a wedding, i.e. the wedding day. The -s is a genitive marker (“of”), and -inn is the attached definite article (“the”) for masculine nouns like dagur.

Why is there no separate word for “the” or “a” in this sentence?

Icelandic handles articles differently from English:

Definite article “the”
- Instead of a separate word, Icelandic usually attaches the definite article to the end of the noun.
- Here, dagur
  - -inn → dagurinn = the day, so brúðkaupsdagurinn = the wedding day.
- That’s why you don’t see a separate word meaning “the”.
Indefinite article “a / an”
- Icelandic simply does not have an indefinite article.
- sérstakur dagur is understood as a special day, even though there is no word for “a”.

So the sentence corresponds to English “The wedding day is a special day”, but Icelandic expresses “the” with a suffix and leaves “a” unspoken.

Why is it sérstakur dagur and not some other form like sérstaka dag or sérstakur dagurinn?

Adjectives in Icelandic agree with the noun in gender, number, and case, and they also change depending on whether the noun is definite or indefinite.

dagur is:
- masculine
- singular
- nominative (subject/complement form)
- indefinite (no “the” attached)

Therefore, the adjective takes the masculine nominative singular, indefinite form:

Masculine nominative singular (indefinite) of sérstakur = sérstakur
So we get sérstakur dagur = a special day

Some contrasts:

sérstaka dag – likely accusative singular (e.g. “on a special day”), not used here because this is not an object.
sérstaki dagurinn – that would be “the special day”, with the adjective also in a definite form; here we need a special day, not the special day.

In this sentence, we are saying:

Brúðkaupsdagurinn (the wedding day)
er sérstakur dagur (is a special day)

So the part sérstakur dagur must be indefinite nominative to match the meaning.

Why is it brúðkaupsdagurinn with -inn at the end? How does that relate to dagur?

The key noun inside the compound is dagur (day), which is a masculine noun. Its nominative singular forms are:

dagur – day
dagurinn – the day

The definite article “the” for masculine nouns is usually -inn:

maður → maðurinn (man → the man)
hestur → hesturinn (horse → the horse)
dagur → dagurinn (day → the day)

When dagur appears inside a compound like brúðkaupsdagur, we add the definite ending to the whole compound:

brúðkaupsdagur – wedding day
brúðkaupsdagurinn – the wedding day

So -inn here is exactly the same definite ending you see on a simple noun like dagurinn.

Could I also say Brúðkaupsdagur er sérstakur dagur? What would be the difference in meaning?

Yes, you can say:

Brúðkaupsdagur er sérstakur dagur.

This changes the meaning slightly:

Brúðkaupsdagurinn er sérstakur dagur.
→ The wedding day is a special day.
This usually refers to one specific wedding day that both speaker and listener know about (for example: our wedding day).
Brúðkaupsdagur er sérstakur dagur.
→ A wedding day is a special day.
This is a general statement about any wedding day, like a proverb or general truth.

So the choice between brúðkaupsdagurinn and brúðkaupsdagur is the same kind of choice as between “the wedding day” and “a wedding day” in English: specific vs general.

Can I drop the word dagur and just say Brúðkaupsdagurinn er sérstakur?

Yes, you can say:

Brúðkaupsdagurinn er sérstakur.

This means:

The wedding day is special.

Here, sérstakur is used on its own as a predicative adjective, describing brúðkaupsdagurinn directly.

Difference in nuance:

Brúðkaupsdagurinn er sérstakur.
→ Focus on the day itself being special.
Brúðkaupsdagurinn er sérstakur dagur.
→ Literally “The wedding day is a special day”. It sounds a bit more emphatic and slightly more formal or explanatory, similar to English using the full “is a special day” rather than just “is special”.

Both are perfectly correct; which one you use is mostly a stylistic choice.

What case are the nouns brúðkaupsdagurinn and dagur in, and why?

Both nouns here are in the nominative singular:

brúðkaupsdagurinn – nominative singular, definite
dagur (in sérstakur dagur) – nominative singular, indefinite

Reason: the verb vera (to be, here er) is a linking verb (a copula). In Icelandic, just like in many other languages:

The subject is in the nominative.
The thing the subject is identified with (the complement) is also in the nominative.

So in:

Brúðkaupsdagurinn er sérstakur dagur.

we have:

Subject: Brúðkaupsdagurinn → nominative.
Subject complement: sérstakur dagur → also nominative.

You do not put dagur into accusative or another case after er.

Can I change the word order, for example say Sérstakur dagur er brúðkaupsdagurinn?

Yes, Icelandic word order is more flexible than English, especially for emphasis, but there are limits.

Your example:
- Sérstakur dagur er brúðkaupsdagurinn.
  This is correct and natural.
  It means the same as the original, but emphasises “a special day”:
  - Literally: “A special day is the wedding day.”
  - Often used when you start by talking about special days in general, then specify that the wedding day is such a day.
Unnatural order:
- Brúðkaupsdagurinn er dagur sérstakur.
  This is not natural Icelandic. Adjectives normally go before the noun they modify in this kind of phrase.
General rule:
- Basic neutral order in a simple statement is Subject – Verb – Complement:
  - Brúðkaupsdagurinn (S) er (V) sérstakur dagur (C).
- You can sometimes put the complement first for emphasis:
  - Sérstakur dagur (C) er (V) brúðkaupsdagurinn (S).

But you cannot freely scramble adjective and noun inside a phrase; sérstakur must stay before dagur.

How do you pronounce brúðkaupsdagurinn and sérstakur dagur? Any tricky sounds for English speakers?

Yes, there are a few sounds that may feel unfamiliar:

Stress
- Icelandic almost always stresses the first syllable:
  - BRÚÐ‑kaups‑da‑gurinn
  - SÉRS‑ta‑kur da‑gur
ð in brúð‑
- ð (eth) is a soft “th”, like “this” or “breathe”.
- So brúð sounds roughly like “brooth” (with rounded Icelandic ú, like a long oo).
au in brúðkaup‑
- au is a diphthong, often approximated as [öy] or [øy], something like French “eu”
  - English “y”:
    - brúð‑kaup ≈ “brooth-koip”, but with the Icelandic vowel quality.
g in dagur
- In dagur, the g is a regular hard g, like in “go”: DAH‑gur.
-urinn
- -urinn is roughly -u-rin:
  - u like the u in “put” (but a bit more rounded),
  - followed by rinn (rolled or tapped r).

A rough English-like approximation (not perfect but helpful):

brúðkaupsdagurinn ≈ BROOTH-koyps-DAH-gur-in
sérstakur dagur ≈ SYEHR-sta-kur DAH-gur

Listening to native audio is very helpful here, because some vowels and the r are quite different from English.

Why aren’t the nouns capitalised, like Brúðkaupsdagurinn or Dagur? In German or English I’d expect capital letters somewhere.

Icelandic capitalisation rules are closer to English than to German, but with one important point:

Only proper nouns (names of people, places, etc.) are capitalised:
- Ísland (Iceland), Reykjavík, Jón, María.
Common nouns are not capitalised:
- dagur (day), brúðkaup (wedding), bók (book), maður (man).

So:

brúðkaupsdagurinn – a common noun phrase (“the wedding day”) → no capital.
If it were a name, like Brúðkaupsdagurinn as the title of a book or a film, then you would capitalise it, but that’s a different usage.

In a normal sentence, writing Brúðkaupsdagurinn er sérstakur dagur. with a capital B for brúðkaupsdagurinn is only because it’s the first word of the sentence, not because it’s a noun.