This is the 661st most frequent Finnish word.
nuori
Young.
In this sentence, 'nuori' is used as an adjective describing the noun 'oppilas' (student), indicating youth.
Nuori oppilas luki kirjaa.
The young student was reading a book.
Here, 'nuoria' is the plural partitive form of 'nuori,' used as an adjective to describe the plural noun 'he' (they).
He olivat nuoria ja täynnä unelmia.
They were young and full of dreams.
In this sentence, 'Nuori' is used as a noun, abstractly referring to the concept of youth in general.