This is the 14300th most frequent Turkish word.
okunduğunu
"That is/was read."
"Okunduğunu" here conveys that something ('the book') was read, formulated in a reported speech structure.
Kitabın öğrencilere okunduğunu duyduk.
We heard that the book was read to the students.
"Okunduğunu" expresses the action of reading (passive voice) as detected or understood by the subject.
Mektubun okunduğunu hissettim.
I felt that the letter was read.
"Okunduğunu" denotes that the article underwent the action of being read, within the context of the meeting.