El otro día viajé.

In this sentence, el otro día is a very common expression meaning the other day.

It usually refers to some recent day in the past, without being very specific. It does not normally mean a clearly identified day like last Tuesday. It is more vague, like when English speakers say the other day.

Because el otro día works as a fixed expression.

• el otro día = the other day
• otro día by itself often means another day or some other day

So the article el is important here. It helps create the idiomatic meaning.

Viajé is the preterite, which is used for a completed action in the past.

So El otro día viajé presents the trip as a finished event:

• I traveled the other day

If you said viajaba, that would be the imperfect, which usually gives a different idea, such as:

• an ongoing past action
• a habitual action
• background information

For example:

• Cuando era niño, viajaba mucho. = When I was a child, I used to travel a lot.

In your sentence, the speaker is talking about one completed trip, so viajé fits better.

Viajé is first person singular in the preterite:

• I traveled

It comes from the verb viajar = to travel.

A quick comparison:

• yo viajo = I travel / I am traveling
• yo viajé = I traveled

The accent mark shows where the stress goes and also helps identify the verb form.

• viajé is stressed on the last syllable: via-JÉ
• It is the yo form of the preterite

This written accent is normal for many yo preterite forms of -ar verbs:

• hablé
• compré
• viajé

Without the accent, it would not be the correct standard spelling.

Usually, no.

Spanish often leaves out subject pronouns when the verb already makes the subject clear. Since viajé already means I traveled, yo is not necessary.

• El otro día viajé. = normal, natural
• Yo viajé el otro día. = also correct, but it may add emphasis or contrast

For example, you might use yo if you want to stress I:

• Yo viajé, pero mi hermano no. = I traveled, but my brother didn’t.

Yes. That is completely natural.

Both are correct:

• El otro día viajé
• Viajé el otro día

The difference is mostly one of focus or rhythm.

• El otro día viajé starts by setting the time frame
• Viajé el otro día starts with the action

In everyday speech, both word orders are common.

It can do both, depending on context.

Viajar is a broad verb meaning to travel. In a sentence like this, it often suggests that the speaker went on a trip or traveled somewhere, even if the destination is not mentioned.

If you want to add more detail, you can:

• El otro día viajé a México. = The other day I traveled to Mexico.
• El otro día viajé por trabajo. = The other day I traveled for work.

Usually it refers to a fairly recent time in the past, but it is still somewhat flexible.

In many conversations, it means something like:

• recently
• a few days ago
• the other day

It is intentionally vague. If you want to be specific, Spanish would usually use an exact time expression instead:

• ayer = yesterday
• el lunes pasado = last Monday
• hace tres días = three days ago

It is pronounced roughly like bee-ah-HEH in much of Latin America, with the stress on the last syllable.

A few pronunciation notes:

• v and b sound very similar in Spanish
• j sounds like a strong h sound in English, but harsher
• the final é is stressed

So:

• viajé → via-JÉ

And the whole sentence is roughly:

• El otro día viajé → el OH-troh DEE-ah via-HEH

Yes, absolutely. El otro día viajé is natural and correct in Latin American Spanish.

It is a simple, everyday sentence that a native speaker could easily say in conversation. The exact pronunciation of some sounds may vary by country, but the grammar and wording are widely understood across Latin America.