From The Free On-line Dictionary of Computing (19 January 2023):
hop
1. <messaging> One point-to-point transmission in a series
required to get a message from point A to point B on a store
and forward network. On such networks (including UUCPNET
and FidoNet), an important inter-machine metric is the hop
count of the shortest path between them. This can be more
significant than their geographical separation.
Each exclamation mark in a bang path represents one hop.
2. <networking> One direct host-to-host connection forming
part of the route between two hosts in a routed network
such as the Internet. Some protocols place an upper limit
on the hop count in order to detect routing loops.
3. <jargon, networking> To log in to a remote computer,
especially via rlogin or telnet. "I'll hop over to foovax
to FTP that."
(1997-06-25)