This is the 15778th most frequent Turkish word.
toplanacağı
"Toplanacağı" means "that will be gathered/assembled/collected."
Here, "toplanacağı" is used to indicate the future gathering of individuals in a specific place.
Toplantıya katılacak kişiler büyük salonda toplanacağı için hazırlıklar yapılıyor.
Preparations are underway because the participants of the meeting will gather in the large hall.
In this sentence, "toplanacağı" is used to describe the future collection or assembling action involving books.
Kitapların toplanacağı masaları düzenlememiz gerekiyor.
We need to arrange the tables where the books will be collected.
The usage of "toplanacağı" in this example is about the future convening or meeting of the committee.