Definitivno ćemo danas isploviti.

Ćemo means we will.

In Croatian, the future tense is often made with:

• a form of htjeti (ću, ćeš, će, ćemo, ćete, će)
• plus the infinitive of the main verb

So in this sentence:

• ćemo = we will
• isploviti = to set sail

Together, ćemo isploviti = we will set sail.

A full set is:

• ja ću
• ti ćeš
• on/ona/ono će
• mi ćemo
• vi ćete
• oni/one/ona će

Because Croatian normally forms the future with an auxiliary plus an infinitive, unlike English, which often uses will + verb.

So:

• we will sail → ćemo ploviti
• we will set sail → ćemo isploviti

This is completely normal Croatian structure.

You may also see future forms written together in some cases when the infinitive loses its final -i, for example:

• pisati → pisat ću

But with word order like this sentence, ćemo isploviti is the standard clear form.

Isploviti means to set sail, to sail out, or to depart by boat/ship.

It is built from the verb ploviti = to sail / to navigate on water, with the prefix is-, which adds the idea of going out / departing.

So isploviti is not just to be sailing around. It specifically suggests:

• leaving port
• starting a voyage
• sailing out

That is why it matches English set sail very well.

Because Croatian often omits subject pronouns when they are not needed.

The verb form ćemo already tells you the subject is we.

So:

• Definitivno ćemo danas isploviti.
• literally: Definitely will-we today set sail.
• natural English: We will definitely set sail today.

You could add mi for emphasis:

• Mi ćemo danas definitivno isploviti.

But normally it is unnecessary.

Croatian word order is more flexible than English word order.

English strongly prefers:

• We will definitely set sail today.

Croatian can move parts around more freely for emphasis, rhythm, or style:

• Definitivno ćemo danas isploviti.
• Danas ćemo definitivno isploviti.
• Definitivno danas ćemo isploviti. (possible, though less natural in many contexts)
• Isplovit ćemo danas definitivno. (different style/register)

In your sentence, the order sounds natural and emphasizes definitely / for sure at the start.

This is connected to an important Croatian rule: short unstressed words such as ću, ćeš, će, ćemo, ćete, će often appear in the second position in the clause. These are called clitics.

In:

• Definitivno ćemo danas isploviti.

the first element is Definitivno, so the clitic ćemo comes right after it.

This kind of placement is very common in Croatian and may feel unusual to English speakers.

Compare:

• Danas ćemo isploviti.
• Sutra ćemo krenuti.
• Sigurno ćemo doći.

The future auxiliary often wants that early, second-position spot.

Usually, yes: definitivno commonly means definitely, certainly, or for sure.

In this sentence, it strongly confirms the action:

• Definitivno ćemo danas isploviti.
• We will definitely set sail today.

A small note: because definitivno looks so much like English definitively, learners sometimes overthink it. In everyday Croatian, it very often functions just like English definitely.

Danas means today.

It gives the time of the action:

• danas = today
• sutra = tomorrow
• jučer = yesterday

So:

• Definitivno ćemo danas isploviti.
• We will definitely set sail today.

Croatian often places time expressions quite freely, so you may also see:

• Danas ćemo definitivno isploviti.

Both are natural, with slightly different emphasis.

Isploviti is perfective.

That matters because Croatian verbs often come in aspect pairs:

• ploviti = imperfective, focusing on the process/state of sailing
• isploviti = perfective, focusing on the completed departure / starting point of the voyage

In future tense, perfective verbs are very common when talking about a single completed action:

• Danas ćemo isploviti. = We will set sail today.

If you used ploviti, the meaning would shift more toward we will be sailing or we will sail (as an activity), not specifically we will depart.

The negative is:

• Definitivno nećemo danas isploviti.
• We definitely will not set sail today.

Here:

• nećemo = we will not

So the future auxiliary changes:

• ćemo → nećemo

Examples:

• Ćemo isploviti. = We will set sail.
• Nećemo isploviti. = We will not set sail.

Yes, you could.

Both are understandable and natural:

• Definitivno ćemo danas isploviti.
• Definitivno ćemo isploviti danas.

The difference is mostly one of focus and flow.

• ... danas isploviti keeps today closely tied to the action before the final verb.
• ... isploviti danas may place a little more emphasis on today at the end.

Croatian allows this kind of variation much more than English does.

A simple learner-friendly pronunciation guide would be:

deh-fee-nee-TEEV-noh CHEH-moh DAH-nahs ees-PLOH-vee-tee

A few key sounds:

• č / ć are not the same, but many learners first just need to know that ć in ćemo is a soft ch-like sound.
• j in Croatian sounds like English y.
• vowels are usually clear and pure:
  • a as in father
  • e as in bed (but steadier)
  • i as in machine
  • o as in more (without a glide)
  • u as in flute

If your pronunciation is consistent and clear, native speakers will understand you even before you fully master č vs ć.

Yes, absolutely.

It sounds natural and idiomatic, especially in a context involving:

• a ship
• a boat
• a ferry
• a sailing trip
• a naval or maritime setting

It expresses confidence that departure will happen today.

Depending on context, a native speaker might also say things like:

• Sigurno ćemo danas isploviti. = We will surely set sail today.
• Danas ćemo definitivno isploviti.
• Sto posto ćemo danas isploviti. (more colloquial: *We’re 100% setting sail today)*

So your sentence is perfectly good Croatian.