This is the 10908th most frequent Turkish word.
değiller
"Değiller" means "they are not."
The word 'değiller' is used to express negation in the plural and third person, indicating 'not' being or doing.
Onlar öğrenci değiller.
They are not students.
Here, 'değiller' negates the location or position of the subject ('books') in the plural third person.
Kitaplar masanın üstünde değiller.
The books are not on the table.
In this sentence, 'değiller' describes negation of the state or condition for plural third-person subjects ('these people').