This is the 14473rd most frequent German word.
koreanische
"Koreanische" means "Korean" (adjective).
The word 'koreanische' is used here in its plural form to describe films originating from Korea.
Ich interessiere mich für koreanische Filme.
I am interested in Korean films.
Here, 'koreanisches' is an adjective agreeing with the neuter singular noun 'Restaurant'.
Wir besuchten ein koreanisches Restaurant in der Stadt.
We visited a Korean restaurant in the city.
In this instance, 'koreanische' modifies the singular feminine noun 'Kultur' to denote it as being specific to Korea.