This is the 12388th most frequent Russian word.
картин
The word "картин" is the genitive plural form of "картина," which means "paintings" or "pictures" in English.
The word 'картин' is the plural genitive case of the noun 'картина', meaning 'painting'. It is used here to indicate possession or collection, as in 'of paintings'.
Я коллекционирую старинные картины.
I collect antique paintings.
In this sentence, 'картин' again is in the plural genitive case and is used as an object in an implying prepositional structure such as 'несколько' (several).
В музее представлено несколько уникальных картин.
There are several unique paintings presented in the museum.
Here 'картин' is once more the plural genitive case of 'картина', providing information about the type of work being done — restoration of paintings.