What it means
Said when someone was a tiny kid, barely taller than a bug. It’s a nostalgic way to say you’ve known them forever, back when they were still in short trousers and causing chaos. The grasshopper bit just hammers the point home: if your knees were only that high, you were properly small.
Usage examples
"I’ve known him since he was knee high to a grasshopper, tearing round his grandma’s yard with scruffy knees. Now he’s got a mortgage and back pain."
"I have been coming to this bakery since I was knee-high to a grasshopper, the smell takes me straight back."
"Look at him captaining the team now, and I remember him knee-high to a grasshopper chasing pigeons in the square."
Where it comes from
A grasshopper is tiny to begin with, so being only knee-high to one makes you smaller than small, a comic measure of littleness. Mostly used looking back, I have known him since he was knee-high to a grasshopper, meaning since he was a wee child barely off the ground.
Other ways to say it
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