haywire

n. Wire used in baling hay.

adj. Informal

1. Mentally confused or erratic; crazy: went haywire over the interminable delays.
2. Not functioning properly; broken.

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Word History: From the use of baling wire for makeshift repairs

Why should the word for something as functional and mundane as haywire have come to be applied to something that is not functioning properly or to a person who is crazy? It would seem a story of semantics gone haywire. Haywire is a compound of the words hay and wire, originally simply denoting wire used to bale hay or straw. The term is first recorded as a noun in a debate in the Canadian House of Commons (1917), so it is a Canadianism or, since it appeared soon thereafter in a U.S. publication, a North Americanism. We find an earlier (1905) attributive use in the phrase hay wire outfit, a term used contemptuously for poorly equipped loggers. What lies behind this term is the practice of making repairs with haywire. Haywire is found in other contexts with the general sense "makeshift, inefficient," from which come the extended senses "not functioning properly" and "crazy."

.... American Heritage, http://www.thefreedictionary.com/haywire