Jury rigging refers to makeshift repairs or temporary contrivances, made with only the tools and materials that happen to be on hand. Originally a nautical term, on sailing ships a jury rig is a replacement mast and yards improvised in case of damage or loss of the original mast.
The phrase "jury rigged" has been in use since at least 1788. However, the adjectival use of "jury" in the sense of makeshift or temporary dates from at least 1616, when it appeared in John Smith's A Description of New England. It appeared again, in a similar passage, in Smith's more extensive The General History of Virginia, New-England, and the Summer Isles published in 1624.
There are several theories about the origin of this usage of "jury":
- From the Latin adjutare ("to aid") via Old French ajurie ("help or relief").
- Contraction in the nautical tradition for injury
While ships typically carried a number of spare parts (e.g., items such as topmasts), the lower masts, at up to one meter in diameter, were too large to carry spares. So a jury mast could be various things. Ships always carried a variety of spare sails, so rigging the jury mast once erected was mostly a matter of selecting appropriate size. Contemporary drawings and paintings show a wide variety of jury rigs, attesting to the creativity of sailors faced with the need to save their ships. Example jury-rig configurations are:
- A spare topmast
- The main boom of a brig
- To replace the foremast with the mizzenmast: mentioned in W. Brady's The Kedge Anchor (1852)
- The bowsprit set upright and tied to the stump of the original mast.
The Jury mast knot is often mentioned as a method to provide the anchor points for securing makeshift stays and shrouds to the new mast. However, there is a lack of hard evidence regarding the knot's actual historical use.
Although ships were observed to perform reasonably well under jury rig, the rig was quite a bit weaker than the original, and the ship's first priority was normally to steer for the nearest friendly port and get replacement masts.
Another source of this term comes from World War Two; in this case, a pun-like play on words. Advancing Allied forces plundering abandoned German bases found a use for emptied metal gasoline cans, nicknamed "Jerry Cans" after the slang term for German. Engineers and mechanics, enduring major supply shortages to the front lines, would jerry-rig the metal from the canisters for use in repairing a damaged hull, fusilage, or any easily fabricated equipment part.
- The phrase "jerry-built" has a separate origin and implies shoddy workmanship not necessarily of a temporary nature.
- "Jiggered" is derived from "jerry-rigged". Although this has come into more common usage, it is still a pejorative term used to denote a poor quality short-lasting fix.
- The folk etymology is that "Jerry-rigged" was employed by World War II British troops to refer to the German use of scavenged parts to keep vehicles and weapons functional, from the use of "Jerry" as a pejorative term for German soldiers.
- "Jimmy rig" is the more intense version of jury rig, a temporary fix that is not as well done and more likely to fail.
- To "MacGyver" something is to rig up something in a hurry to make an item work, from the U.S. television show of the same name and its title character, who would often use such homemade rigs.
- The Oxford English Dictionary, Volume V, H-K (Oxford: Clarendon Press, 1933; corrected reprinting 1966), 637.
- Captaine Iohn Smith, The Generall Historie of Virginia, New-England, and the Summer Isles (London: Michael Sparkes, 1624; 2006 UNC digital republication), 223. (Online edition.)
- Note that in the orthography of Early Modern English 'I' was often used in place of 'J', thus the actual quote from Smith(1624) reads, "...we had re-accommodated a Iury-mast to returne for Plimoth..."
- Robert K. Barnhart, ed., Barnhart dictionary of etymology, (New York: H. W. Wilson Company, 1988), 560.
- Charles Hamel, "Investigations on the Jury Mast Knot"    Accessed 2007-02-22.
- William and Mary Morris, Morris Dictionary of Words and Phrase Origins, 2nd Edition (New York: HarperCollins, 1988), 321-322.
- "'jerry-built'/'jury-rigged'". alt.usage.english Word Origins FAQ. Accessed 2006-05-25.
- John Harland, Seamanship in the Age of Sail (Naval Institute Press, 1984)