This is the 10193rd most frequent Turkish word.
başvurusuna
"Başvurusuna" means "to his/her/its application" in English.
Here, 'başvurusuna' indicates belonging—it refers to Ali's application (başvuru) and its context within the sentence.
Ali üniversite için yaptığı başvurusuna cevap bekliyor.
Ali is waiting for a response to his application submitted for the university.
In this context, 'başvurusuna' directs the action towards his application, showing interaction with the application itself.
Son anda başvurusuna ek belgeler ekledi.
At the last moment, he added extra documents to his application.
Here, 'başvurusuna' specifies the target of the reply, indicating to which application the positive response was given.