Search us!

Search The Word Detective and our family of websites:

This is the easiest way to find a column on a particular word or phrase.

To search for a specific phrase, put it between quotation marks.






Comments are OPEN.

We deeply appreciate the erudition and energy of our commenters. Your comments frequently make an invaluable contribution to the story of words and phrases in everyday usage over many years.

Please note that comments are moderated, and will sometimes take a few days to appear.



shameless pleading





Dry Run

OK, when I say “Go,” flap your arms and run toward the edge.

Dear Word Detective:  My wife has been going through a tough project at work and as part of the work, they were attempting a “dry run” to see if things will work in a test environment.  On a car trip, I had to ask, “What was the origin of  ‘dry run'”?  One of our ideas was it was from plumbing:  to make sure the pipes didn’t leak, they put air in and tested the joints.  Could we be close? — Rich Harrington.

Wow.  Some people actually discuss word and phrase origins while they’re on a road trip?  In our car the dialog seems to focus on questions like “Is that noise coming from our car?” or “Do you smell something burning?”  Other big hits include “Did you see what that guy just did?”, often followed by “How could you not have seen what that guy just did?” and the ever-popular “Maybe I should drive.”  By the way, did you know that the driver of a car has the absolute legal power to determine what music is played in the car?  It’s in the US Constitution.

A “dry run,” of course, is a rehearsal or practice session conducted to make certain that a system works or that a procedure can be carried out without serious mistakes.  While practice may not make perfect, it does make it a lot less likely that you’ll be scanning the help wanted ads the day after your snazzy new escalator pitches your boss into the koi pool.

Of course calling it a “dry run,” rather than just a “practice run” or the like immediately raises the question of why “dry,” and whether there might be such a thing as a “wet run.”   The first citation for “dry run” in the “practice” sense listed by the Oxford English Dictionary (OED)  is from 1941, although the OED does list earlier uses of “dry run” to mean a dry creek bed or desert arroyo.  But since no one has ever come up with a plausible scenario linking the two senses we can safely assume that the two uses are unrelated.

As a matter of fact, until just a few years ago, no one had come up with a truly convincing explanation for the origin of “dry run,” and the only theories proposed were halfhearted attempts to connect the phrase to such phrases as “dry heaves” (slang for unproductive vomiting).  But in 2004, Douglas Wilson, a poster to the mailing list of the American Dialect Society (ADS), offered (and, more importantly, documented) what I believe is a slam-dunk answer to the “dry run” question.
It turns out that “dry run” comes from the jargon of fire departments (where a “run” is a dispatch of a fire brigade).

Beginning in the late 19th century, fire departments in the US began conducting practice sessions where engines were dispatched and hoses deployed, but water was not pumped, thus making the exercises literally “dry” runs.  Public exhibitions and competitions between departments also typically centered on such “dry runs.”  Conversely, a real run to a “working fire” where water was pumped was known as a “wet run.”  In his posting to the ADS list, Doug Wilson found instances of this use of “dry run” dating back to 1893.  Just when the term came into more general use meaning “practice session” is uncertain, but it seems to have been after “dry run” was widely used in the US Armed Services during World War II.

13 comments to Dry Run

  • Dale Murphy

    In the world of Hydroelectric Power which I frequent, when we have taken a machine off-line for overhaul we run it “in the dry” (that is, without water) as we are testing it to make sure that it won’t fly apart with water in it and drown all hands. We call such an effort a “dry run”.


  • amar

    this is superb! I was speculating that the phrase was a result of the prohibition. so trucks would try and sneak across the border – and dry run to test.

  • Don Frost

    Now it may just be me, but I was watching Dukes of Hazzard on TV tonite and Boss Hogg used the term “dry run” on there in the episode about him dying (was a mistake) but anyway, I decided to see where the term came from. Thinking about how they were ridge runners during the prohibition I assumed it may have something to do with that. I see that amar was thinking the same thing and it does seem very plausible. Being that the first dictionary appearance was in ’41 makes it even more so. I have some shiners still alive in my family and I will look into it more but for now I think it is safe to say “Dry Run” (Dry=Prohibition) means to do a test run with no shine in the car.

  • anonym

    I thought it had something to do with running printing presses without ink…

  • Pirate

    I was thinking it was much older than that, stemming from pirates or bootleggers running blockades with their holds empty or “dry” in advance of running through with their holds full of bootleg rum!

  • J.L.M.

    A “wet run” sounds like someone didn’t make it to the bathroom in time. :/

  • Thomas Guerra

    Well, before gluing furniture or any wood-work project together it is standard practice to clamp the whole thing up without glue to see if everything is square. Once you establish that everything fits together correctly by this “dry run”, you glue it.

  • Ale

    Thanks for the explanation, since long time ago I was thinking about the meaning of dry run ! BTW: I got used to it in finance processes.

  • Singaporean

    “Dry run” is used in the Singapore Army to indicate any training or exercise done without live ammo. In Singapore, the popular belief is that the term “dry run” originated from usage in the military (of which all male citizens are conscripted to). In the past generations of the 1960s and 1970s, many conscripts were Chinese-language educated, and the Army was their first immersion of an English-language environment. Their accent made them pronounce “trial run” as “dry run”. They also referred to themselves as “Chinese-educated”, which the English-schooled colleagues would hear as “Chinese helicopter”. Hence this became derogatory term that was used to refer to all soldiers who were Chinese-educated.

  • i’m a furniture maker and the term dry run has always been used to describe a practice assembly of a piece of furniture with out the glue in the joints i.e. dry.

    this may seem odd but in reality glue starts to set very quickly and in many situations (particularly if it is warm) you may only have a few minutes to get everything assembled and the clamps in place. the dry run allows you to set all of the clamps and lay out all of the pieces so that the full glue up runs smoothly. at the best of times glue ups are very stressful (you may have several weeks of work invested in making all the components and cutting all the joints) so anything to reduce the stress is very helpful. i don’t know if this is the true entomology of the phrase but it may be.

    hope this helps.


  • Cylinder-head-nut

    The term ‘dry run’ is often used in engineering, as shown above in the case of printing.

    In an automotive sense, internal combustion engines require oil for lubrication. Oil is housed in the ‘sump’ at the bottom of the engine and is pumped to the moving parts to provide lubrication. To initially test an engine in the factory (prior to delivery), sometimes a tiny amount of oil is applied to strategic parts of the engine such as the main bearings, and the engine is started ‘dry’ (without the sump being filled with oil). The engine will be run for a few seconds only before being shut down ready for delivery to the customer, who will then fill the sump with oil prior to use.

    A ‘dry run’ such as this in the factory proves the the engine works. I always assumed that THIS was the origin of the term, but it appears it is only one example of a ‘dry run’. Interesting topic. Thank you to all who have commented so far.

  • Bill Clinton

    Moonshiners and people who transported alcohol illegally made a dry run in a transport vehicle as a decoy to lead revenuers away from the vehicle making the wet run.

    The dry vehicle had no alcohol but the wet vehicle did. The movie “Thunder Road” with Robert Mitchum was loosely based on the activities of real life moon runners.

    Opinions vary as to whether Shiners were the first to use the terms dry-run and wet-run and whether Shiners caused dry-run to become widely used.

Leave a Reply to Singaporean Cancel reply




You can use these HTML tags

<a href="" title=""> <abbr title=""> <acronym title=""> <b> <blockquote cite=""> <cite> <code> <del datetime=""> <em> <i> <q cite=""> <s> <strike> <strong>

Please support
The Word Detective

by Subscribing.


Follow us on Twitter!




Makes a great gift! Click cover for more.

400+ pages of science questions answered and explained for kids -- and adults!