What it means
Means you found out via gossip, whispers, or second-hand chat rather than anything official. The grapevine is that invisible network of coworkers, neighbours, and group chats that spreads news at warp speed, usually with a few extra toppings added. Handy when you want plausible deniability, risky if you start repeating it like it's fact.
Usage examples
"Heard through the grapevine the landlord’s selling up, so I’m lining up a new place. No official email yet, but everyone’s whispering."
"I heard through the grapevine that they are closing the old factory."
"Do not ask how I know, let us just say it came through the grapevine."
"I heard through the grapevine they're gutting the whole department, so now everyone's acting normal in that weird panic way."
"Word came through the grapevine that Jay quit on Friday, and somehow his desk was cleared before lunch."
Where it comes from
It comes from grapevine telegraph, a US Civil War era phrase for rumour travelling person to person instead of through official channels. The image stuck because a grapevine twists, branches, and tangles up, which is pretty much exactly what gossip does before it reaches you.
