Bussissa istuessani kuuntelen suomenkielistä podcastia.

Istuessani means while I am sitting or more naturally while sitting.

It comes from the verb istua (to sit) and uses a Finnish structure often called the second infinitive in the inessive, plus a possessive suffix:

• istua = to sit
• istuessa = while sitting
• istuessani = while I am sitting / while sitting

The ending -ni shows that the subject is I.

So in this sentence:

• Bussissa istuessani = while I am sitting on the bus

This structure is very common in Finnish when you want to say while doing something.

Bussissa is the inessive form of bussi (bus). The inessive ending -ssa/-ssä often means in.

So:

• bussi = bus
• bussissa = in the bus / on the bus

In English we usually say on the bus, but Finnish uses the form that is literally more like in the bus.

Here, bussissa tells you the location where the action happens:

• Bussissa istuessani = while sitting on the bus

This is a very common question.

• bussissa = in/on the bus (location: you are inside it)
• bussilla = by bus or sometimes at the bus depending on context

Examples:

• Menen töihin bussilla. = I go to work by bus.
• Istun bussissa. = I am sitting on the bus.

In your sentence, the idea is not mainly the method of travel, but the place where you are sitting and listening. That is why bussissa is the natural choice.

Because Finnish often leaves out personal pronouns when the verb already shows the person clearly.

Here:

• kuuntelen = I listen
• the ending -n tells you the subject is I

Also:

• istuessani contains -ni, which also points to my / I

So Finnish does not need minä here. You could say Minä kuuntelen..., but it would usually sound more emphatic, like I listen.

Kuuntelen is the 1st person singular form of kuunnella (to listen).

• kuunnella = to listen
• kuuntelen = I listen

Finnish verb endings usually tell you who is doing the action, so minä is optional.

Compare:

• kuuntelen = I listen
• kuuntelet = you listen
• kuuntelee = he/she listens

So the sentence already clearly means that I am the one listening.

They are both in the partitive singular:

• suomenkielinen podcast = a Finnish-language podcast
• suomenkielistä podcastia = a Finnish-language podcast (partitive)

This happens because kuunnella usually takes a partitive object.

So:

• kuuntelen musiikkia = I listen to music
• kuuntelen radiota = I listen to the radio
• kuuntelen podcastia = I listen to a podcast

The adjective has to match the noun in case and number, so:

• suomenkielinen → suomenkielistä
• podcast → podcastia

This is very normal Finnish object marking.

Suomenkielistä means Finnish-language or in Finnish.

It comes from:

• suomen = of Finnish / of Finland here referring to the language suomi
• kielinen = language-

So suomenkielinen podcast means a podcast in the Finnish language.

This is different from suomalainen:

• suomenkielinen podcast = a podcast in Finnish
• suomalainen podcast = a Finnish podcast, perhaps made in Finland or by Finns

A podcast could be suomalainen but not suomenkielinen, or suomenkielinen but not necessarily suomalainen.

Both are possible, but they feel a little different.

• Bussissa istuessani kuuntelen...
• Kun istun bussissa, kuuntelen...

The version with istuessani is more compact and elegant. It is very common in written Finnish and also understood perfectly well in speech, though kun istun may feel a bit more conversational.

A key point is that istuessani normally has the same subject as the main verb. In this sentence, both actions are done by the same person:

• I am sitting
• I listen

So the form works perfectly.

No, Finnish word order is fairly flexible.

The original sentence is:

Bussissa istuessani kuuntelen suomenkielistä podcastia.

But you could also say:

• Kuuntelen bussissa istuessani suomenkielistä podcastia.
• Kuuntelen suomenkielistä podcastia bussissa istuessani.

These all mean roughly the same thing, but the emphasis changes slightly.

The original order puts the situation first:

• While sitting on the bus...

Then it tells you what happens:

• ...I listen to a Finnish-language podcast.

That makes it a very natural sentence.

Yes, literally it does mean while sitting.

So the sentence paints a fairly specific picture: you are seated on the bus and listening to a podcast.

If you wanted a broader meaning like while traveling by bus, Finnish might use a different expression, for example something based on matkustaa (to travel):

• Matkustaessani bussissa... = while traveling on the bus

So istuessani is not just about being on the bus; it specifically refers to the action or state of sitting.