This is the 9209th most frequent Turkish word.
vatanı
The Turkish word "vatanı" means "his/her/its homeland" or "his/her/its fatherland."
In this sentence, "vatanı" refers to the homeland, used in an accusative form to denote the object of the action 'to protect.'
Vatanı korumak her vatandaşın görevidir.
Protecting the homeland is every citizen's duty.
Here, "vatanını" shows possession (his homeland) and serves as the direct object of the verb 'to miss.'
O, vatanını özleyen bir gurbetçiydi.
He was an expatriate who missed his homeland.
"Vatanı" indicates a locative presence (homeland) in relation to the idea of doing something 'for it' and functions as the object of the preposition in context.