This is the 1565th most frequent Turkish word.
konuyu
The word "konuyu" means "the topic" or "the subject" (in the accusative case) in English.
In this sentence, 'konuyu' refers to 'the topic' as a specific direct object that was discussed.
Bir süre daha konuşarak konuyu daha iyi anladılar.
They understood the topic better by discussing it for a while.
Here, 'konuyu' indicates 'the topic' which is the direct object of the verb 'explained'.
Öğretmen konuyu öğrencilere iyi açıklamıştı.
The teacher had explained the topic well to the students.
In this case, 'konuyu' refers to 'the topic' as the direct object of the verb 'open up' indicating the subject matter to be discussed.