This is the 7249th most frequent Russian word.
водителя
The Russian word "водителя" means "driver" (genitive or accusative singular form).
Here, 'водителя' is in the Genitive case as it represents possession or attribution in the context of giving advice.
Я дал вежливый совет водителя.
I gave polite advice to the driver.
In this context, 'водителя' is in the Genitive case because it's the object of the action related to detention.
Полиция задержала водителя за нарушение правил.
The police detained the driver for breaking the rules.
Here, 'водителя' is in the Accusative case as it is the direct object of the verb 'видел' (saw).