What it means
Higgledy-piggledy means all jumbled up, in a complete muddle with no order whatsoever. Books shelved higgledy-piggledy, a drawer of cables all higgledy-piggledy, a queue that went higgledy-piggledy the moment the doors opened. It is chaos described with a grin, the kind of mess that is more comic than catastrophic.
Usage examples
"The market stalls were set up all higgledy-piggledy, you never knew if the next one sold cheese or socks."
"After the move, the books sat higgledy-piggledy on the shelf for months before anyone bothered to sort them."
"The kids tidied their room by shoving everything higgledy-piggledy into the wardrobe and slamming the door."
Where it comes from
A rhyming reduplication from the fifteen hundreds, most likely built on pig. Pigs crowd into their pen in a heaving, shoving jumble with no order at all, and that squirming tangle of trotters gave English the perfect picture of total disarray.
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