Uppsagnarfresturinn er langur.

Because Icelandic makes very frequent use of compound nouns. What English often expresses as two words, Icelandic often packs into one.

Here, uppsagnarfresturinn is built from:

• uppsögn = resignation, dismissal, termination
• frestur = deadline, period of time, grace period

Together, uppsagnarfrestur means notice period. Then the definite article is added at the end, giving uppsagnarfresturinn = the notice period.

That -ar- comes from the genitive form of uppsögn.

A very common pattern in Icelandic compounds is:

• first noun in a linking/genitive form
• second noun as the main noun

So:

• uppsögn → uppsagnar-
• frestur = period

This gives uppsagnarfrestur, literally something like period of notice/termination.

Because uppsagnarfresturinn is the definite form: the notice period.

In Icelandic, the definite article is usually attached to the end of the noun instead of being a separate word.

Compare:

• uppsagnarfrestur = a notice period
• uppsagnarfresturinn = the notice period

So the -inn ending is doing the job that English the does.

The head noun of the compound is frestur, and frestur is masculine. In Icelandic compounds, the last part usually determines the gender.

You can also see the masculine grammar in the sentence:

• uppsagnarfresturinn has a masculine definite ending
• langur is the masculine singular form of long

So both the noun phrase and the adjective point to masculine singular.

Because Icelandic adjectives agree with the noun they describe in gender, number, and case.

Here, uppsagnarfresturinn is:

• masculine
• singular
• nominative

So the adjective must also be masculine singular nominative:

• langur = masculine
• löng = feminine
• langt = neuter

Since this adjective comes after er, it is still matching the subject.

It is in the nominative case because it is the subject of the sentence.

The structure is:

• uppsagnarfresturinn = subject
• er = is
• langur = predicate adjective

With vera (to be), the predicate adjective normally agrees with the subject, so langur is also nominative masculine singular.

Er is the present tense, 3rd person singular form of að vera, which means to be.

So:

• ég er = I am
• þú ert = you are
• hann / hún / það er = he / she / it is

In this sentence, uppsagnarfresturinn is singular, so er is the correct form.

Yes. Just like English long, Icelandic langur can refer either to physical length or to duration.

So in this sentence, langur means that the notice period lasts a long time, not that it is physically long.

A rough learner-friendly pronunciation is:

UP-sak-nar-fres-tu-rin

A few helpful points:

• The stress in Icelandic almost always falls on the first syllable.
• In combinations like gn, the g is not pronounced like English g in go.
• The u in Icelandic does not sound exactly like English oo or uh, so it is best learned by listening to native audio.

A more phonetic approximation would be something close to UP-sak-nar-fres-tu-rin, with the first syllable clearly stressed.

Yes. This is the most neutral and natural word order for a simple statement:

• subject: Uppsagnarfresturinn
• verb: er
• adjective/complement: langur

So it follows the same basic pattern as English The notice period is long.

Icelandic can change word order for emphasis, but this version is the standard, unmarked one.

Yes. That would mean The notice period is very long.

Here, mjög is an adverb meaning very, and it modifies the adjective:

• langur = long
• mjög langur = very long

That is a very natural extension of the sentence.

They are related, but they are not the same thing.

• uppsögn = the resignation, dismissal, or termination itself
• uppsagnarfrestur = the notice period connected with that termination

So one is the act/event, and the other is the time period that follows or is required around it.