Learn Hardcore Norwegian: Stolryggen og armlenet justeres. - The back of the chair and the armrest are adjusted.

Breakdown of Stolryggen og armlenet justeres.

Why are stolryggen and armlenet written as single words?

Because Norwegian normally writes compound nouns as one word.

So where English often uses separate words like chair back or arm rest, Norwegian usually combines them into one noun.

Why does stolryggen end in -en, but armlenet ends in -et?

Those endings show the definite singular, but the form depends on the noun’s grammatical gender.

stolrygg is a common-gender noun, so the definite form is stolryggen
armlene is a neuter noun, so the definite form is armlenet

So the difference is not about meaning; it is about noun gender.

Where is the word the in this sentence?

In Norwegian, the is usually attached to the end of the noun instead of being a separate word.

So:

and

That is why there is no separate word for the here.