What it means
Means you're so shocked you go silent with your mouth hanging open. Gob is your mouth and to be smacked is to be walloped, so the surprise has basically slapped the words out of you. Use it for big news, mad prices, or a plot twist that leaves you staring into space.
Usage examples
"I opened the payslip and nearly dropped my brew, they'd actually given me a bonus. I just stood there, proper gobsmacked, like a stunned muppet."
"I was gobsmacked when they read out the winner, I genuinely thought there had been a mistake with the envelope."
Where it comes from
From gob, the mouth in British and Irish slang, plus smacked: so shocked it is as if someone clapped you across the mouth. Gobsmacked is utter speechless astonishment, the jaw-on-the-floor kind. Big across Britain, Ireland and the southern hemisphere, it is the word for news so surprising it knocks the words right out of you.
Other ways to say it
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