Hjemkomsttidspunktet er sent.

Yes. Norwegian very often makes long compound nouns where English would use several words.

hjemkomsttidspunktet can be broken down like this:

• hjem = home
• hjemkomst = return home / homecoming
• tidspunkt = point in time / time
• hjemkomsttidspunkt = return-home time / time of returning home
• hjemkomsttidspunktet = the return-home time

The most important part is the last part, tidspunkt, because the last part decides the basic meaning and grammar of the whole compound.

Because Norwegian usually puts the definite article at the end of the noun as a suffix.

Here:

• tidspunkt = a time / a point in time
• tidspunktet = the time / the point in time

Since this is a compound noun, the definite ending goes on the whole compound:

• hjemkomsttidspunkt = return-home time
• hjemkomsttidspunktet = the return-home time

So English uses a separate word (the), but Norwegian often uses an ending like -en, -a, or -et.

Because hjemkomsttidspunktet is a neuter singular noun, and the adjective agrees with it.

The adjective is:

• sen for masculine/feminine singular
• sent for neuter singular
• sene for plural

Since tidspunkt is neuter, you get:

• et tidspunkt
• tidspunktet er sent

So sent is the correct form here.

Good question. In Norwegian, adjectives behave differently depending on where they are used.

Here, sent is a predicative adjective: it comes after er and describes the subject.

• Hjemkomsttidspunktet er sent.

In this position, the adjective agrees mainly with gender and number, not with definiteness in the same way as before a noun.

Compare:

• det sene hjemkomsttidspunktet = the late return time
  
  • here the adjective comes before the noun, so you use sene
• hjemkomsttidspunktet er sent = the return time is late
  
  • here the adjective comes after er, so you use sent

So definite sene is used before the noun, but predicative sent is used after er.

Here it is an adjective, because it describes the noun hjemkomsttidspunktet.

• Hjemkomsttidspunktet er sent.
  Here sent describes the return time.

But sent can also be used adverbially in other sentences:

• Vi kommer sent hjem. = We come home late.

So the same form can look the same, but its job in the sentence is different.

By itself, sent means late.

If you want to say too late, Norwegian usually says:

• for sent = too late

So:

• Hjemkomsttidspunktet er sent. = The return time is late.
• Hjemkomsttidspunktet er for sent. = The return time is too late.

That little word for makes an important difference.

The sentence has a very basic Norwegian main-clause pattern:

• Hjemkomsttidspunktet = subject
• er = verb
• sent = predicative adjective

So the structure is:

Subject + verb + complement

This is completely normal. Also remember that Norwegian main clauses follow the V2 rule, which means the finite verb is in the second position. If you move another element to the front, the verb still stays second:

• I dag er hjemkomsttidspunktet sent. = Today the return time is late.

It is understandable and correct, but it sounds a bit formal or administrative because hjemkomsttidspunktet is a heavy, technical-looking compound.

You might see something like this in:

• schedules
• rules
• travel information
• official writing

In everyday speech, people would often say something simpler, such as:

• Vi kommer hjem sent. = We’re coming home late.
• Tidspunktet vi kommer hjem på er sent. = The time we come home is late.

So the original sentence is correct, but a bit more formal than casual conversation.

A useful rough guide for an English speaker is:

yem-komst-tee-pungk-steh

A few notes:

• hj in hjem is usually pronounced like a y sound in many varieties of Norwegian.
• tid sounds like teed.
• punkt has a clear k/t ending cluster.
• The whole word is long, but native speakers still treat it as one unit.

You do not need perfect pronunciation right away; the main challenge is recognizing that it is just a normal Norwegian compound noun.