The correct definition for this being the (Cockney) slang for face.
He got a punch right in the mooey, the cheeky...
also Taken from the film Nil by Mouth (1997)
"Never stopped him going to the pub, though. No, he was well enough to do that. Now, one day, right, he's staggering across the pub pissed from the night before. He's gone over, crunch, right on his mooey, like a fucking ironing board. His hooter's around here, his railings all over the fucking place."
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