This is the 536th most frequent Finnish word.
sisällä
"Inside" or "indoors."
The word 'sisällä' means 'inside' and indicates the location of something within another object.
Kirja on kaapin sisällä.
The book is inside the cupboard.
Here, 'sisällä' specifies the interior environment of the house where the described situation applies.
Sisällä talossa oli lämmin tunnelma.
Inside the house, there was a warm atmosphere.
In this sentence, 'sisällä' is used to point to the contents within a book, illustrating its use for describing the insides of abstractions or concepts.