This is the 367th most frequent Persian word.
سراسر
"سراسر" means "all over," "throughout," or "entire."
In this case, 'سراسر' denotes the entirety of the path.
سراسر مسیر هموار بود.
The entire path was smooth.
Here, 'سراسر' indicates a duration covering the entire day.
سراسر روز به مطالعه مشغول بودم.
I was busy studying throughout the day.
In this example, 'سراسر' is used to describe complete coverage of an area.