This is the 6510th most frequent Russian word.
buick
The word "Buick" is not Russian; it refers to an American automobile brand.
Here, 'Buick' is used as a proper noun referring to a specific brand of car.
Я увидел классический Buick на автопарковке.
I saw a classic Buick in the parking lot.
In this instance, 'Buick' is used to indicate the make of the car we are traveling in.
Мы решили поехать в отпуск на нашем старом Buick.
We decided to go on vacation in our old Buick.
Here, 'Буик' (Buick) refers to the company or brand that manufactures the cars.