Higgledy-piggledy

“In confusion or disorder. The expression comes (in the late 16th century) from a rhyming jingle, probably with reference to the irregular herding together of pigs.” The Oxford Dictionary of Phrase and Fable.

“Although we don't know when exactly higgledy-piggledy first appeared in print, we do know that the word has been around since before 1600. John Florio's A Worlde of Wordes, an English-Italian dictionary first published in 1598, used higgledy-piggley as a defining term for the Italian word alla rinfusa, along with two other examples of reduplication, pell-mell and helter-skelter.” Merriam-Webster.com Dictionary.