Itu hanya kebetulan.

Word by word:

• itu = that / sometimes it, depending on context
• hanya = only, just
• kebetulan = coincidence

So a very literal gloss is:

• That only coincidence

Natural English is:

• That’s just a coincidence.

Malay often leaves out the verb to be in simple sentences like this.

So:

• Itu kebetulan = That is a coincidence
• Dia guru = He/She is a teacher
• Rumah itu besar = That house is big

In everyday Malay, this is completely normal.

In more formal Malay, you may sometimes see ialah with noun phrases, but in ordinary speech it is usually omitted.

Literally, itu means that.

However, when translating into natural English, it can sometimes come out as it, especially when you are referring back to a situation that was just mentioned.

So depending on context:

• Itu hanya kebetulan = That’s just a coincidence
• or It’s just a coincidence

Malay often uses itu to point to something already known, already mentioned, or obvious from the situation.

Malay does not have articles like a, an, and the the way English does.

So:

• kebetulan can mean a coincidence or the coincidence, depending on context.

If you really want to add the idea of one/a, you can use satu:

• Itu hanya satu kebetulan

But this is not necessary. In many cases, the version without satu sounds more natural.

Hanya means only, just, or merely.

In Itu hanya kebetulan, it weakens the importance of what is being talked about:

• Itu kebetulan = That is a coincidence
• Itu hanya kebetulan = That is only / just a coincidence

So the speaker is saying there is no deeper meaning behind it.

Yes. Common alternatives are:

• cuma = very common in speech, just / only
• sahaja or saja = only / just

Examples:

• Itu cuma kebetulan.
• Itu kebetulan sahaja.
• Itu kebetulan saja.

All are natural, but the tone is slightly different:

• hanya = neutral, slightly more formal than cuma
• cuma = very common and conversational
• sahaja / saja = also common; saja is more casual

Kebetulan means coincidence or something that happens by chance.

In this sentence, it is a noun:

• Itu hanya kebetulan = That is just a coincidence

It often refers to two things matching up accidentally, without planning or intention.

Yes, it is built from the root betul, and it has the affixes ke-...-an.

However, for a learner, the safest approach is to learn kebetulan as a whole vocabulary item meaning:

• coincidence
• chance occurrence

This is because its actual meaning in modern Malay is not something you can always guess just from betul.

Yes.

Besides meaning coincidence as a noun, kebetulan can also be used in a way that means coincidentally or by chance.

For example:

• Kebetulan, saya ada di sana.
  Coincidentally / As it happened, I was there.

So the same word can function a little differently depending on the sentence.

In Itu hanya kebetulan, it is clearly the noun meaning coincidence.

Yes. It is completely natural and easy to understand.

It sounds neutral and normal in everyday conversation.

Some very common alternatives are:

• Itu cuma kebetulan.
• Itu kebetulan saja.

All of these mean roughly the same thing, with only small differences in tone or formality.