De kalder det kortmisbrug.

It can be either one, and this sentence by itself is ambiguous.

Why?

• de = they
• De = formal/polite you in more old-fashioned or very polite Danish

But because the word is at the beginning of the sentence, it is capitalized anyway, so you cannot tell from the capital D alone.

So:

• De kalder det kortmisbrug. could mean They call it card misuse/fraud.
• It could also mean You call it card misuse/fraud. in a formal/polite sense.

In modern everyday Danish, they is much more common than formal De, but the real meaning depends on context.

Kalder is the present tense of at kalde = to call.

So:

• at kalde = to call
• kalder = call / calls / are calling, depending on context

Danish present tense is very often formed with -er, so this is a very common pattern.

Examples:

• Jeg kalder = I call
• Du kalder = you call
• De kalder = they call / formal you call

Because det is the thing being called something. It means it here.

The pattern is:

kalde + object + label/name

So in this sentence:

• De = they / formal you
• kalder = call
• det = it
• kortmisbrug = the label they give it

So the structure is basically:

They call it X.

Without det, the sentence would not express the same idea.

The sentence uses a very common Danish pattern where one noun/pronoun is the object, and the final word tells you what that object is called.

Structure:

Subject + verb + object + complement

Here that gives us:

• De = subject
• kalder = verb
• det = object
• kortmisbrug = object complement, the name/category given to det

A similar example is:

• Jeg kalder ham Peter. = I call him Peter.

So kortmisbrug is not a second ordinary object. It is the name/term applied to det.

Because Danish normally writes compound nouns as one word.

So:

• kort
  • misbrug → kortmisbrug

This is extremely common in Danish.

English often writes similar expressions as two words or with a modifier plus noun, but Danish usually joins them into one compound.

A learner should get used to this, because Danish does it all the time.

Yes. Here kort means card.

Danish kort can mean different things depending on context, including:

• card
• map
• short

But in kortmisbrug, the meaning is clearly card, because it combines with misbrug in a way that refers to misuse or fraudulent use of a card.

So this is a good reminder that Danish words can be context-dependent, just like English words can.

Because kortmisbrug is being used as a category/label, and it is also an abstract noun.

After kalde, Danish often uses a noun without an article when you are naming or classifying something:

• De kalder det snyd.
• Vi kalder det held.

That is similar to what is happening here.

If the noun were a countable one, an article might appear:

• De kalder det en fejl. = They call it a mistake.

But kortmisbrug works more like misuse/fraud as a general category, so no article is needed.

Yes, many speakers do say kalde noget for noget, especially in everyday speech.

So both of these can occur:

• De kalder det kortmisbrug.
• De kalder det for kortmisbrug.

However, kalde noget noget is often treated as the more neutral or more standard written pattern.

So for a learner:

• without for = very safe, standard choice
• with for = also common in real usage

It is normal Danish main clause word order.

Danish usually follows the V2 rule in main clauses, meaning the finite verb tends to come in the second position.

Here:

• De = first element
• kalder = second element

So the sentence is perfectly regular.

You can see the same pattern if another element comes first:

• I dag kalder de det kortmisbrug. = Today they call it card misuse.

Notice that the verb kalder still stays in second position.

Yes. In a subordinate clause, Danish does not keep the same main-clause V2 pattern.

For example:

• Jeg ved, at de kalder det kortmisbrug. = I know that they call it card misuse.

Here de kalder appears in the more ordinary subject-verb order after at.

This is useful because learners often first meet a simple main clause like De kalder det kortmisbrug, and then wonder why word order looks different after words like at, fordi, or når.