This is the 815th most frequent Finnish word.
italian
The Finnish word "italian" is the genitive singular form of "italia," meaning "of Italian" or "of Italy."
In this sentence, 'italiaa' is used to refer to the Italian language in its partitive case, indicating that the person speaks or practices some amount of Italian.
Osaan puhua italiaa.
I can speak Italian.
Here, 'italialaisen' is an adjective derived from 'Italia', used in its singular accusative case to describe the book as being of Italian origin.
Ostin italialaisen kirjan.
I bought an Italian book.
In this instance, 'italialaista' is an adjective in the partitive case to describe the food as being characteristic of Italian cuisine.