This is the 9521st most frequent Russian word.
фнка
It seems there may be a typo in "фнка." If you meant "финка," it refers to a Finnish-style knife or, colloquially, a small blade or dagger.
In this sentence, 'финка' refers to a woman from Finland, used as a noun in the nominative case.
Финка изучает историю своих предков.
The Finnish woman studies the history of her ancestors.
Here, 'финка' refers to a type of Finnish knife, showcasing its use as a noun in a context of objects.
У него есть старинная финка с гравировкой.
He has an antique Finnish knife with engraving.
In this case, 'финки' is the plural form referring to Finnish knives, emphasizing its importance in specific professions or roles.