استنى لحظة.

A good rough pronunciation is istanna laḥza.

A few helpful details:

• استنى is usually pronounced istanna
• the n is doubled, so it sounds like istan-na
• لحظة is often said roughly like laḥza

In fast everyday speech, some speakers reduce the first vowel a bit, so you may also hear something closer to stanna.

Because Arabic writing normally leaves out most short vowels in everyday text.

So in استنى:

• the short i at the beginning is not written
• the doubled n is also not clearly shown unless someone writes a shadda

A more phonetic colloquial spelling is often استنّى, which makes the doubled n easier to see.

It is an imperative verb, meaning it is a command: wait!

Arabic imperatives already include the subject, so you do not need a separate word for you.
So استنى by itself already means wait! addressed to one person.

In this form, it is usually understood as masculine singular unless context says otherwise.

In colloquial spelling, the masculine singular form is often written with final ى: استنى.

That final ى does not mean an ee sound here. In this word, it represents the final -a / -ā sound of the masculine imperative.

You may also see:

• استنى
• استنّى

Both are common informal spellings. Dialect spelling is not fully standardized.

Yes. In Levantine, the imperative changes by gender and number.

Common forms are:

• استنّى — to one man
• استنّي — to one woman
• استنّوا — to more than one person

In very casual texting, people are sometimes loose with spelling, but these are the usual forms to learn.

A rough pronunciation is laḥza.

The main points are:

• ح is a strong Arabic ḥ, not the normal English h
• ظ is often pronounced close to an emphatic z, and in everyday Levantine it may sound very close to plain z
• the final ة is pronounced -a here

So for most learners, laḥza is a useful approximation.

Because Arabic does not use a separate indefinite article like English a/an.

So:

• لحظة = a moment
• اللحظة = the moment

The noun by itself can be indefinite, so no extra word is needed.

This is colloquial Levantine Arabic, not formal Modern Standard Arabic.

A more formal equivalent would usually be:

• انتظر لحظة — to one man
• انتظري لحظة — to one woman

Many Arabic speakers outside the Levant will still understand استنى, but it sounds spoken and regional rather than formal.

Not necessarily. It is very normal in everyday speech.

Whether it sounds fine or rude depends mostly on:

• your tone of voice
• the situation
• who you are speaking to

With friends, family, coworkers, or in quick everyday situations, it is completely natural.
If you want to sound softer or more polite, you can say:

• استنى شوي
• استنى لحظة لو سمحت
• ممكن تستنى لحظة؟

Yes. Very common alternatives include:

• استنى شوي — wait a bit
• استنى ثانية — wait a second
• استنى دقيقة — wait a minute

These are all natural in conversation. لحظة is common, but it is not the only noun you can use after استنى.

Yes. لحظة! by itself is very common.

It can mean:

• one moment!
• just a second!
• hold on!

People often say it when:

• answering the door
• looking for something
• asking someone to pause briefly