What it means
A cheeky way to say keep this quiet or don’t repeat it. You tack it on before a bit of gossip or a confession, as if the nearest lamppost is sworn to secrecy too. It’s pretty old-fashioned and often said tongue-in-cheek, like the classic between you, me and the gatepost, but it still gets a laugh.
Usage examples
"Between you, me and the lamppost, I scoffed the last custard cream and blamed the dog. If Nan clocks it, I’m in deep trouble."
"Between you, me and the lamppost, I reckon they're moving away, but don't you dare say I told you."
"She got the promotion, but between you, me and the lamppost, half the team is already looking elsewhere."
Where it comes from
The phrase plays a little joke: a secret should stay between you and me, so the speaker ropes in the nearest lamppost as a silent third party, as if street furniture could keep schtum. It belongs to a whole family of these, with the gatepost and the bedpost as the older cousins.
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