This is the 12308th most frequent Russian word.
итальянцы
It means "Italians."
The word 'итальянцы' refers to the people of Italy collectively in this sentence.
Итальянцы славятся своей кухней, особенно пастой и пиццей.
Italians are famous for their cuisine, especially pasta and pizza.
Here, 'итальянцами' (instrumental case) is used to describe specific individuals of Italian nationality.
Я познакомился с итальянцами, которые живут в соседнем доме.
I met Italians who live in the neighboring house.
In this sentence, 'итальянцы' generalizes all Italian people in terms of their cultural habits or interests.