A rendszám az autón van.

A is the Hungarian definite article, meaning the.

So:

• a rendszám = the license plate

Hungarian has two forms of the:

• a before most consonant sounds
• az before vowel sounds

That is why the sentence has both a and az:

• A rendszám
• az autón

Because autón begins with a vowel sound, Hungarian uses az instead of a.

So:

• a ház = the house
• az autó = the car

After adding the ending, autón still begins with a vowel, so it stays:

• az autón = on the car

Rendszám means license plate or registration number/plate.

It is a single Hungarian word:

• rend = order/system
• szám = number

Together, rendszám is the normal word for a car’s plate number.

Because Hungarian adds a suffix to show location.

Here, -n means something like on.

• autó = car
• autón = on the car

So az autón literally means on the car.

This is called the superessive case, which is used for being on the surface of something.

In this word, yes, the relevant ending is basically -n, but Hungarian often inserts or changes sounds when suffixes are added.

With autó, the result is:

• autó → autón

You can think of it as the normal on-location form of the noun.

Other examples:

• asztal = table → asztalon = on the table
• szék = chair → széken = on the chair
• autó = car → autón = on the car

So the exact shape of the ending can vary, but the function is the same: on something.

That is a very common question.

Hungarian often omits van in the present tense when the sentence links a subject to a noun or adjective:

• A ház nagy. = The house is big.
• Ő tanár. = He/She is a teacher.

But when talking about location or existence, Hungarian normally uses van:

• A könyv az asztalon van. = The book is on the table.
• A rendszám az autón van. = The license plate is on the car.

So here van is needed because the sentence tells us where something is.

Hungarian word order is flexible, but the neutral, natural order for a basic location sentence often puts van at the end:

• A rendszám az autón van.

This feels like:

• topic: A rendszám = as for the license plate
• location: az autón
• verb: van

Putting van at the end is very normal in simple statements like this.

Yes, you could. It is grammatical, but the emphasis changes.

• A rendszám az autón van.
  Neutral meaning: The license plate is on the car.

• Az autón van a rendszám.
  This puts more attention on the car or the location, something like:
  It’s on the car that the license plate is.

Hungarian word order often shows focus or what is being highlighted, not just basic grammar.

Because both nouns are definite:

• A rendszám = the license plate
• az autón = on the car

English also often uses the with both nouns in a sentence like this:

• The license plate is on the car.

Hungarian does the same here.

It is in the superessive case, which expresses on something.

The superessive usually answers the question:

• Hol? = Where?

Examples:

• az asztalon = on the table
• a falon = on the wall
• az autón = on the car

So in this sentence, autón marks the location.

Yes. In this sentence, az autón naturally means on the car.

That makes sense because a license plate is attached to the outside surface of the car.

Hungarian often uses its on-surface location form in situations where English also uses on.

A simple English-friendly approximation is:

• aw rend-saam az ow-too-n vawn

A few helpful notes:

• a = a short aw
• á = a longer aa
• sz = s sound, as in see
• au in autó sounds similar to ow in cow
• ó is a long o

So:

• rendszám sounds roughly like rend-saam
• autón sounds roughly like ow-tohn

Yes. Like most Hungarian nouns, rendszám can take many endings.

For example:

• a rendszám = the license plate
• a rendszámot = the license plate (object)
• a rendszámon = on the license plate
• a rendszámnak = to the license plate

Hungarian grammar relies heavily on suffixes, so learning nouns together with common case endings is very useful.

Yes, it shows several important basics at once:

• definite article: a / az
• noun: rendszám
• location with a case ending: autón
• present tense of to be for location: van

So it is a very useful model for making similar sentences, such as:

• A könyv az asztalon van. = The book is on the table.
• A kabát a széken van. = The coat is on the chair.
• A táska az autóban van. = The bag is in the car.