اختي نامت بدري، بس انا نمت بعد الفيلم.

A natural pronunciation is:

okhti namet badri, bas ana nimt baʿd il-film

You may also see slightly different transliterations, such as ukhti for اختي or el-film for الفيلم. That is normal; transliteration is not fully standardized.

Word by word:

• اختي = okhti = my sister
• نامت = namet = she slept / she went to sleep
• بدري = badri = early
• بس = bas = but
• انا = ana = I
• نمت = nimt = I slept / I went to sleep
• بعد الفيلم = baʿd il-film = after the movie

اختي means my sister.

It is built like this:

• أخت / اخت = sister
• -ي = my

So instead of using a separate word for my, Arabic often adds a suffix directly to the noun.

Examples:

• اخت = sister
• اختي = my sister
• اخته = his sister
• اختها = her sister

Both can be seen.

• أختي is the more careful spelling
• اختي is very common in casual writing, especially in dialect and online

In informal Egyptian Arabic writing, people often leave out the hamza in words where the meaning is still obvious. So اختي and أختي mean the same thing here.

They are different past-tense forms of the same verb:

• نام = he slept
• نامت = she slept
• نمت = I slept

This verb is one of the common Arabic verbs where the vowel changes when endings are added. So even though both forms come from نام, the shape of the word changes in conjugation.

This is very normal in Arabic, not something unique to this sentence.

Yes.

• نامت already means she slept
• نمت already means I slept

Arabic verbs usually include the subject information inside the verb itself. That means the independent pronoun is often optional.

So in this sentence:

• اختي نامت = my sister slept
• أنا نمت = I slept

The word أنا is included here mostly for contrast: but I...

بدري means early.

In Egyptian Arabic, it is a very common everyday word. It functions like an adverb here, describing when the sleeping happened.

So:

• نامت بدري = she slept early / she went to sleep early

It is much more natural in everyday Egyptian speech than using a more formal Standard Arabic expression.

In real usage, it often means went to sleep early or went to bed early, not just slept early in a literal English sense.

That is because نام can refer to the act of falling asleep or going to sleep, depending on context.

So:

• اختي نامت بدري very naturally means my sister went to sleep early

Here, بس means but.

It is a very common Egyptian Arabic word with a few meanings depending on context:

• بس = but
• بس = only / just
• بس! = enough! / stop!

In this sentence, it clearly introduces contrast between two clauses, so the meaning is but:

• اختي نامت بدري، بس انا نمت بعد الفيلم
• My sister went to sleep early, but I slept after the movie

Because it adds emphasis and contrast.

Arabic often includes the independent pronoun when the speaker wants to highlight who is being contrasted with someone else.

So:

• بس نمت بعد الفيلم = possible, but less explicit
• بس انا نمت بعد الفيلم = but I slept after the movie

The أنا helps underline the contrast between my sister and me.

بعد الفيلم means after the movie.

It is made of:

• بعد = after
• الفيلم = the movie

So literally: after the movie

A few useful notes:

• الفيلم has الـ because it means the movie
• فيلم is a loanword, so it may look familiar
• In Egyptian pronunciation, الفيلم is often said as il-film or el-film

So:

• بعد الفيلم = baʿd il-film = after the movie

Yes. Arabic word order is flexible, especially in spoken dialect.

For example, you could also say:

أنا نمت بعد الفيلم، بس اختي نامت بدري

That would still be natural and correct. The difference is mostly about emphasis and what you mention first.

The original sentence starts with اختي first, so it sets up your sister as the first topic, then contrasts that with you.