This is the 5364th most frequent Turkish word.
kişilerdir
"Persons" or "individuals."
Kişilerdir here refers to persons and is the plural form used in context with extraordinary individuals described in books.
Bu kitaplarda bahsedilen bireyler, sıra dışı kişilerdir.
The individuals mentioned in these books are extraordinary persons.
In this sentence, kişilerdir emphasizes the significance of individuals contributing to societal development.
Toplumun gelişiminde katkıda bulunan kişiler, önemli kişilerdir.
People who contribute to the development of society are important individuals.
The word kişilerdir is used to highlight the value artists and scientists bring to society.