This is the 8905th most frequent Polish word.
setki
"Setki" in Polish means "hundreds" in English.
Here, 'setki' is used as a noun meaning 'hundreds', indicating a large number of birds.
Widziałem setki ptaków na niebie.
I saw hundreds of birds in the sky.
In this sentence, 'setki' is used to express a repeated action done many times, again meaning 'hundreds' as a quantifier.
Lubię setki razy oglądać ten film.
I like watching this movie hundreds of times.
Here, 'setki' quantifies 'interesujących zdjęć' (interesting pictures), emphasizing the abundance.