When something goes haywire, it's out of control or completely chaotic. You'll sense that things have gone haywire at a birthday party if suddenly the young guests are having a crazed water gun fight indoors.

A riot is an extreme example of things going haywire, when people get angry enough about something that they ignore rules and laws, breaking windows and setting things on fire. A less serious case of things gone haywire could be a flock of chickens escaping an enclosure, running loose in your vegetable garden. The literal, and original, meaning of haywire is "wire used to bind hay." The wire's "springy unpredictability" led to today's common definition.

Primary Meanings of haywire

wire for tying up bales of hay
informal or slang terms for mentally irregular
Full Definitions of haywire

n wire for tying up bales of hay

Type of:
ligament made of metal and used to fasten things or make cages or fences etc

adj informal or slang terms for mentally irregular

around the bend, balmy, barmy, bats, batty, bonkers, buggy, cracked, crackers, daft, dotty, fruity, kookie, kooky, loco, loony, loopy, nuts, nutty, round the bend, wacky, whacky
afflicted with or characteristic of mental derangement

adj not functioning properly

“has gone completely haywire
amiss, awry, wrong
malfunctioning, nonfunctional
not performing or able to perform its regular function

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