Hidden YAML keyword: wait

[Beliefg]

I've discovered this keyword wait, that seems to be the only wait to get:
websocket.messages_sent: ....................................................... 2
websocket.send_rate: ........................................................... 1/sec

but it does not appear documented anywhere. Can someone provide insight into it? To provide greater context, I came across while trying to listen to an open socket that is sending messages triggered elsewhere. Here is the scenario:

scenarios:
- name: Capture WS message
engine: ws # Enable the Websocket engine
flow:
- connect: '{{ target }}/{{ userKey }}&sessionId={{ userSessionId }}&officeKey={{ officeKey }}'
- log: 'Connected to WebSocket'
- think: 1
- log: "Waiting for message..."
- wait: 10 # Wait for up to 10 seconds for the message