This is the 744th most frequent Hungarian word.
őszi
"Őszi" means "autumnal" or "relating to autumn" in English.
The word 'őszi' is used as an adjective to describe 'falevelek' (leaves), indicating their association with the autumn season.
Az őszi falevelek szépek.
The autumn leaves are beautiful.
Here, 'őszi' modifies 'ruhákat' (clothes), referring to clothing suitable for or associated with autumn.
Őszi ruhákat vettem a boltban.
I bought autumn clothes at the store.
In this case, 'ősz' is a noun referring to the autumn season itself, and 'őszi' could be understood implicitly describing this seasonal beauty.