Que azar, perdi o ônibus e agora vou chegar tarde.

Que azar is a very common exclamation in Portuguese. It means something like What bad luck! or How unlucky!

Here, que is part of an exclamatory pattern:

• Que azar! = What bad luck!
• Que pena! = What a shame!
• Que absurdo! = How absurd!

So que here is not introducing a full question. It is being used to make an exclamation.

In everyday Brazilian Portuguese, azar usually means bad luck or misfortune.

So:

• Que azar! = What bad luck!
• Foi azar. = It was bad luck.

Be aware that in some contexts dar azar can mean to bring bad luck, and azar can appear in idiomatic expressions. But in this sentence, it simply means bad luck.

Portuguese often leaves out the subject pronoun when it is clear from the verb.

• Perdi already tells you the subject is I, because it is the first-person singular form of perder in the preterite.
• So perdi o ônibus naturally means I missed the bus.

You could say eu perdi o ônibus, but adding eu usually gives extra emphasis, contrast, or clarity.

For example:

• Perdi o ônibus. = neutral
• Eu perdi o ônibus, não ela. = I missed the bus, not her

Yes, perder often means to lose, but it can also mean to miss in many situations.

Examples:

• Perdi a chave. = I lost the key.
• Perdi o ônibus. = I missed the bus.
• Perdi o filme. = I missed the movie.

So in Portuguese, the same verb often covers both lose and miss, depending on context.

Portuguese uses definite articles much more often than English does.

So perdi o ônibus is the normal way to say I missed the bus. Even when English might sound less article-heavy, Portuguese often prefers:

• o ônibus
• o carro
• o trem

This is very natural in Portuguese and usually does not need a special reason beyond normal usage.

Perdi is the preterite form of perder.

It is used for a completed action in the past:

• perdi = I lost / I missed

Here it works well because missing the bus is a single completed event.

Compare:

• Perdi o ônibus. = I missed the bus.
• Eu perdia o ônibus com frequência. = I used to miss the bus frequently.

So perdi is the correct choice for one finished event.

Both are possible, but vou chegar tarde is much more common in everyday Brazilian Portuguese.

This structure is:

• ir + infinitive
• vou chegar = I am going to arrive / I will arrive

It is the usual way to talk about the future in speech.

Compare:

• Vou chegar tarde. = very common, natural in conversation
• Chegarei tarde. = correct, but more formal or less conversational

So the sentence sounds natural and modern for spoken Brazilian Portuguese.

Literally, chegar tarde means to arrive late.

So:

• vou chegar tarde = I’m going to arrive late

In English, we often translate that more naturally as I’m going to be late, especially in context.

Portuguese often uses arrive late where English prefers be late.

You could also hear:

• Vou me atrasar. = I’m going to be late.
• Estou atrasado. = I’m late. / I’m running late.

They are related, but they are not used in exactly the same way.

• tarde = late, used especially with verbs like chegar

  • chegar tarde = to arrive late

• atrasado / atrasada = late, delayed, behind schedule

  • Estou atrasado. = I am late.
  • O ônibus está atrasado. = The bus is late.

So in this sentence:

• vou chegar tarde sounds very natural because it refers to arriving late

A closely related alternative would be:

• agora vou me atrasar

Agora means now, but in sentences like this it often works as a discourse marker meaning something like:

• now
• and now
• so now

Here it connects the two events:

1. I missed the bus.
2. As a result, now I’m going to arrive late.

So agora helps show the consequence:

• perdi o ônibus e agora vou chegar tarde
• I missed the bus and now I’m going to arrive late

The comma separates the opening exclamation from the rest of the sentence.

• Que azar, perdi o ônibus...

This is similar to how English might write:

• What bad luck, I missed the bus...

It helps signal a pause after the emotional reaction.

You may also see it written with stronger punctuation:

• Que azar! Perdi o ônibus e agora vou chegar tarde.

That version is also very natural.

Ônibus is pronounced with the stress on the first syllable: Ô-ni-bus.

The accent mark in ô shows:

• the stressed syllable is the first one
• the vowel sound is a closed o

A rough English-friendly guide is:

• OH-nee-boos
  but the final sound is not exactly English boos; it is closer to Portuguese bus with a reduced final vowel sound depending on accent.

The plural is the same in form:

• o ônibus = the bus
• os ônibus = the buses

Yes. There are several natural alternatives, depending on style.

Examples:

• Que azar! Perdi o ônibus e agora vou chegar tarde.
• Droga, perdi o ônibus e vou chegar tarde.
• Perdi o ônibus, então vou chegar tarde.
• Perdi o ônibus e agora vou me atrasar.

They all express a similar idea, but the original sentence sounds completely natural in Brazilian Portuguese.