What is the name of the API that initiates communication with the client itself?

Question

API

Imagine there is a service that parses a website. There is an API, when accessed, to which you can get the parsed data. And what is the correct name when the API itself will initiate sending data to the client? That is, the client has a certain address where data should be dumped as soon as they appear at the service. Something like push, only it seems to have a normal name for this. Tell me, please, but I did not find anything))