This is the 11703rd most frequent Russian word.
завалит
"Завалит" means "will overwhelm," "will block," or "will fail (someone)" depending on the context.
In this sentence, 'завалит' is used informally to mean 'fail' or 'not pass' in the context of taking an exam.
Он завалит экзамен, если не будет готовиться.
He will fail the exam if he does not study.
Here, 'завалит' refers to the snow obstructing or blocking the road, implying a heavy snowfall causing an impassable barrier.
Снег завалит дорогу и никто не сможет проехать.
The snow will cover the road, and nobody will be able to pass.
In this context, 'завалит' is used to describe the act of not successfully completing a task, usually due to negligence or lack of effort.