What does "higgledy-piggledy" mean — and why is it funny?

informal

Meaning

In a confused, disordered, jumbled-up way.

Where it comes from

An English phrase from the 1500s. It is a rhyming reduplication, possibly built on 'pig', from the way pigs huddle together in an untidy heap.

Why it is funny

The humor is that the word is itself a mess. To describe disorder, the phrase reaches for a tumbling, rhyming, slightly piggish noise — the sound is as jumbled as the thing it names.

Used in a sentence

"The books were stacked higgledy-piggledy all over the floor."