This is the 9338th most frequent Turkish word.
yolcunun
"Yolcunun" means "of the traveler" or "the traveler's" in English.
Yolcunun denotes possession of the luggage, indicating it belongs to 'the passenger'.
Yolcunun bavulu otobüsten indirildi.
The passenger's luggage was taken off the bus.
Yolcunun is used here in the nominative case with a possessive suffix, identifying who should be careful.
Yolcunun dikkatli olması gerekiyor.
The passenger needs to be careful.
Yolcunun specifies who the seat belongs to, signifying a link to 'the passenger'.