What it means
A wet blanket is that mate who sucks the air out of the room by moaning, refusing to join in, or acting like fun is a personal insult. The image is simple: throw a wet blanket on a fire and it fizzles out, same with a good night out. Used when someone’s a vibe-killer, not just a bit quiet.
Usage examples
"We were buzzing for karaoke, but Liam turned up being a wet blanket, moaning about the queue, the song choices, and the price of pints."
"Don't be a wet blanket, come dancing with us for one song at least."
"Jess was fully being a wet blanket about the road trip, saying it'd rain, the car'd break down, and nobody'd find parking anyway."
"He's such a wet blanket on nights out, one loud song comes on and suddenly he's acting like the evening's personally offended him."
"Every time the plan gets a bit lively, Tom turns into a wet blanket and starts listing everything that could go wrong."
Where it comes from
It started as the literal thing you'd chuck on a fire to smother it. That image slid into figurative English by the 19th century, so a wet blanket became the person who puts the fun out, cools the mood, and leaves the whole room feeling a bit rain-soaked.
Other ways to say it
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