Идите прочь.

Идите is the imperative form used for:

• more than one person: Go away, all of you
• one person politely/formally: like vous in French or Sie in German

If you were speaking to one person informally, you would say иди прочь.

So:

• иди прочь = to one person, informal
• идите прочь = to several people, or to one person formally

Идите is the imperative of идти, which means to go or to be going on foot.

In this sentence, it means go!

A useful thing to know is that Russian often uses forms of идти in commands even when English would simply say go. So идите is a very normal way to form a command.

Прочь is an adverb meaning something like:

• away
• off
• out of here

So it adds the idea of moving away from the speaker or from a place.

In идите прочь, it intensifies the command: not just go, but go away.

Yes, usually it sounds harsh, dismissive, or angry.

It is not a neutral everyday way to ask someone to leave. It is closer to:

• Go away
• Get out of here
• Be off

Even though идите can be the polite/formal form grammatically, the whole phrase is still usually emotionally strong because of прочь.

Yes. Because идите can be either:

• plural
• or formal singular

So you can say Идите прочь to:

• one person you address formally
• several people

If you are talking to one friend, child, or someone informally, you would normally say Иди прочь instead.

No. Прочь is an adverb, not a preposition.

That means it does not take a noun after it and does not control any case.

So in идите прочь, the structure is simply:

• идите = imperative verb
• прочь = adverb meaning away

Идите прочь is the normal and natural order.

Russian word order is flexible, but not every rearrangement sounds equally natural. In this case, идите прочь is the standard phrasing.

You can also have simply:

• Прочь! = Away! / Get out!

That sounds even sharper and more abrupt.

The stress is:

• идите
• прочь is one syllable

A rough pronunciation guide:

• идите ≈ ee-DEE-tye
• прочь ≈ proch'

A few details:

• the stress in идите is on the second syllable: идИте
• the ч in прочь is soft
• the final ь does not make a separate sound; it softens the consonant before it

Russian has several related verbs that can all translate as go away or leave, but they differ in aspect and nuance.

• идите прочь = go away; direct and forceful
• уходите = leave / go away; often more neutral
• уйдите = leave with emphasis on the completed result

So идите прочь sounds very much like a blunt command to move away from the speaker. It is more emotional than a simple уходите in many contexts.

People do say it, but it often sounds dramatic, angry, or literary rather than mild and everyday.

Depending on context, Russians might more often say things like:

• Уходите! = Leave!
• Убирайтесь! = Get out!
• Пошёл вон! / Пошла вон! = very rude Get out!

So Идите прочь is perfectly understandable and correct, but it has a strong tone.

Yes. Прочь! can stand alone.

By itself it means something like:

• Away!
• Get out!
• Off with you!

Used alone, it is usually very abrupt and emotional. Adding идите makes it a full verbal command, but the forceful feeling remains.