Lakken er rød.

Because Norwegian usually adds the definite article to the end of the noun instead of using a separate word like the.

• lakk = lacquer / paint / varnish
• lakken = the lacquer / paint / varnish

For a masculine singular noun, -en is the normal definite ending.

In this sentence, the is already built into lakken.

That is very common in Norwegian:

• en bil = a car
• bilen = the car

So:

• lakk = lacquer
• lakken = the lacquer

A separate word like the is not needed here.

Er means is.

It is the present tense of å være, which means to be.

So the sentence structure is:

• Lakken = the lacquer
• er = is
• rød = red

Because adjectives in Norwegian agree with the noun in gender and number, even after er.

Here, lakk is a masculine singular noun, so the adjective is rød.

Compare:

• Lakken er rød = The lacquer is red.
• Huset er rødt = The house is red.
  (hus is neuter, so rødt)
• Bilene er røde = The cars are red.
  (plural, so røde)

Lakk is normally masculine in Bokmål.

That matters because gender affects:

• the indefinite article: en lakk
• the definite form: lakken
• adjective agreement in some contexts

In this sentence, the masculine singular noun matches the adjective form rød.

Because in this sentence, rød is not directly attached to the noun. It comes after er and describes the subject. This is called a predicative adjective.

So:

• Lakken er rød = The lacquer is red.

But if you want the adjective directly before the noun, you get a different structure:

• rød lakk = red lacquer
• den røde lakken = the red lacquer

So both positions are possible, but they mean slightly different sentence types.

You would say den røde lakken.

This is a useful contrast:

• Lakken er rød = The lacquer is red.
• den røde lakken = the red lacquer

Notice what changes:

• you add den
• the adjective becomes røde
• the noun stays definite: lakken

This double marking of definiteness is normal in Norwegian.

A rough guide:

• lakken ≈ LAHK-ken
• er ≈ a short unstressed ehr
• rød has the vowel ø, which does not exist in standard English

About ø:

• It is similar to the vowel in French bleu or German schön
• It is not the same as English oo or uh

Also, in many pronunciations, the final d in rød is very weak or silent.

It can mean several related things depending on context, such as:

• lacquer
• varnish
• polish
• a painted surface or finish, especially on a car

So lakken er rød could refer to the red paint finish on something, not just a jar of lacquer.

If you specifically mean nail polish, Norwegian usually says neglelakk.

This is a very basic Norwegian sentence pattern:

• Subject + verb + adjective

So:

• Lakken = subject
• er = verb
• rød = adjective

This is the same basic order as in English:

• The lacquer is red

So for an English speaker, the word order here is very straightforward.