This is the 4345th most frequent Russian word.
блокирует
Blocks.
Here, 'блокирует' is used to describe the action of preventing calls from coming through.
Это приложение блокирует нежелательные звонки.
This application blocks unwanted calls.
'блокирует' in this sentence describes the accident causing an obstruction to the traffic.
Движение на дороге блокирует авария.
The traffic on the road is blocked by an accident.
In this context, 'блокирует' refers to the act of restricting access to something.