This is the 12165th most frequent Turkish word.
gülünün
"Gülünün" means "of the rose" or "the rose's" in English, indicating possession.
Here, 'gülünün' means 'of the rose' and refers to the rose that is growing in the garden.
Bahçede büyüyen gülünün kokusu çok güzel.
The scent of the rose growing in the garden is very beautiful.
In this context, 'gülünün' indicates possession, as in 'the rose that is yours/the rose I gave you.'
Sana hediye ettiğim gülünün yaprakları dökülmüş.
The leaves of the rose I gifted you have fallen off.
Here, 'gülünün' signifies possession and the property of the rose ('the rose you showed me').