בוררות שונה מגישור.

It is pronounced roughly:

borerút shoná mi-gishúr

A more detailed breakdown:

• בוררות — borerút = arbitration
• שונה — shoná = different
• מגישור — mi-gishúr = from mediation / than mediation

So the full sentence sounds like:

borerút shoná mi-gishúr

Because in Hebrew, the verb to be is usually omitted in the present tense.

So:

• בוררות שונה מגישור
  literally: Arbitration different from mediation

But in natural English, that means:

• Arbitration is different from mediation

This is completely normal Hebrew sentence structure.

Here שונה means different.

The pattern is:

• X שונה מ־Y = X is different from Y

So in this sentence:

• בוררות שונה מגישור
  = Arbitration is different from mediation

A useful thing to remember is that Hebrew uses מ־ after שונה, just like English uses from after different.

In Hebrew, many prepositions are attached directly to the following word.

Here the preposition is:

• מ־ = from

So:

• גישור = mediation
• מגישור = from mediation

This is very common in Hebrew. The preposition does not need to stand alone.

Literally, מ־ means from, but after שונה it corresponds to English from in the phrase different from.

So:

• שונה מ־... = different from ...

It is not the normal than used in comparisons like bigger than.
For example:

• גדול מ־... = bigger than ...
• שונה מ־... = different from ...

So in this sentence, מגישור is best understood as from mediation.

Because בוררות is a feminine singular noun, and adjectives in Hebrew normally agree with the noun in gender and number.

So:

• בוררות — feminine singular
• שונה — feminine singular

That agreement is why the sentence is grammatical.

Yes — in unpointed Hebrew spelling, שונה can represent more than one spoken form.

It can be:

• shoné = masculine singular different
• shoná = feminine singular different

In this sentence, you know it is shoná because it agrees with בוררות, which is feminine.

So context tells you how to read it.

Yes. Both are abstract/legal-process nouns.

• בוררות = arbitration
• גישור = mediation

They refer to processes or methods, not to people or concrete objects.
That is one reason the sentence feels very natural without articles in a general statement.

Not necessarily. Hebrew often leaves nouns indefinite when making a general statement.

So:

• בוררות שונה מגישור
  means something like
  Arbitration is different from mediation

This is a general statement about the two concepts.

If you wanted to talk about specific, already-known instances, you might use the definite article:

• הבוררות שונה מהגישור
  = The arbitration is different from the mediation

So the version without ה־ is the natural generic statement.

The dictionary form is:

• גישור

The מ־ is just a prefixed preposition.

So when looking the word up, you should search for גישור, not מגישור.

The root is:

• ג־ש־ר

This root is connected with the idea of bridging or connecting.
That makes sense, because mediation is a process of helping bridge a dispute.

So:

• גשר = bridge
• גישור = mediation

This is a nice example of how Hebrew roots often reflect the core image behind a word.

A very literal gloss would be:

• בוררות — arbitration
• שונה — different
• מגישור — from mediation

So literally:

Arbitration different from mediation

But the natural English translation is:

Arbitration is different from mediation.

The literal gloss helps show the structure, but the normal translation should include is.

Yes. Very much so.

A highly useful pattern is:

• X שונה מ־Y = X is different from Y

For example:

• המצב שונה מהעבר = The situation is different from the past
• הגישה הזאת שונה מהגישה הקודמת = This approach is different from the previous approach

So בוררות שונה מגישור is a good model sentence to remember.