Adjective : an explosion resulting from some unaccounted-for mechanical failure.    From Dictionary.com. 

He's come into large, unaccounted-for sums of money.    From Wordnik.com.  [Sweet Anger]

Should the tariff cover the estimated unaccounted-for water?.    From Wordnik.com.  [Chapter 5] Reference

There was no free time or unaccounted-for moment in the day.    From Wordnik.com.  [Jenn Satterwhite: Fearless in the Face of Addiction] Reference

Nkosio said there were 477 unaccounted-for freedom fighters.    From Wordnik.com.  [ANC Daily News Briefing] Reference

UNIDENTIFIED FEMALE: And he is unaccounted-for at this moment.    From Wordnik.com.  [CNN Transcript Sep 16, 2004] Reference

Secondly, we're always concerned about unaccounted-for trucks.    From Wordnik.com.  [CNN Transcript Oct 12, 2001] Reference

Nationally, unaccounted-for firearms are a huge problem for ATF.    From Wordnik.com.  [Gun dealers often stay in business with new licenses after ATF shuts them down] Reference

Long remained unaccounted-for, and was eventually declared dead on March.    From Wordnik.com.  [Remains Returned List WWII] Reference

"There's that unaccounted-for ten percent that can go for or against you.".    From Wordnik.com.  [Heart Of The Tiger]

Espey was one of the more than servicemen unaccounted-for from the battle at.    From Wordnik.com.  [Remains Returned List WWII] Reference

If you raise your voice, you die; if you make an unaccounted-for move, you die.    From Wordnik.com.  [The Miko]

Nov. and was one of the more than servicemen unaccounted-for from the battle at.    From Wordnik.com.  [Remains Returned List WWII] Reference

Valencio was one of the more than servicemen unaccounted-for from the battle at.    From Wordnik.com.  [Remains Returned List WWII] Reference

In King County alone, there were more than 3,500 unaccounted-for ballots or voters.    From Wordnik.com.  [Look Who] Reference

RICE: We know that there are unaccounted-for Scud and other ballistic missiles in Iraq.    From Wordnik.com.  [CNN Transcript Sep 8, 2002] Reference

Both Fateh and Hamas are known to control and disperse millions of unaccounted-for dollars.    From Wordnik.com.  [Fatahgate: Between Fact and Fiction] Reference

He stayed on his guard, reminding himself that there remained one unaccounted-for highwayman.    From Wordnik.com.  [Ascendance]

The argument that they are only relative requires the existence of unaccounted-for alternatives.    From Wordnik.com.  [Common ancestry passes another test. News at 11. - The Panda's Thumb] Reference

But this implies that the previous measurements suffered from a large, unaccounted-for background.    From Wordnik.com.  [CDF Ghost Muons] Reference

The unaccounted-for work, therefore, amounts to only 1½ per cent. of the calculated available work.    From Wordnik.com.  [Scientific American Supplement, No. 441, June 14, 1884.] Reference

Whether there are any unaccounted-for chemical and biological weapons, only the inspectors can tell.    From Wordnik.com.  [CNN Transcript Feb 8, 2003] Reference

Which leaves seven unaccounted-for weeks for E, and five for M, in case you're not keeping track at home.    From Wordnik.com.  [Why I Can't Handle 21st-Century Mothering] Reference

With the identification of these two servicemen, 2,097 Americans remain unaccounted-for from the Vietnam War.    From Wordnik.com.  [Underwood, Paul G.] Reference

The 1997 Water Resources Study suggests that unaccounted-for water in the BWA's potable water supply approaches 60%.    From Wordnik.com.  [Water profile of Barbados] Reference

The figures for unaccounted-for water suggested "poor management accounting of the system", he told MPs at the time.    From Wordnik.com.  [ANC Daily News Briefing] Reference

An unaccounted-for box with electronics in it is more alarming on a bridge than stuck on the side of a random building.    From Wordnik.com.  [The Boston non-bombs.] Reference

An investigation into those still unaccounted-for determined that Hickok may have been among the Sicard crewmen aboard USS.    From Wordnik.com.  [Remains Returned List WWII] Reference

And this brought me to the, as yet, unaccounted-for Japanese -- I call them such for lack of a more definite characterization.    From Wordnik.com.  [The Paternoster Ruby] Reference

Along with their missing craft, rotating, fully formed images of the unaccounted-for trio appeared above the projection surface.    From Wordnik.com.  [Drowning World]

There are 12 unaccounted-for victims on Japan's official list of abductees, but Tokyo believes the true count may be in the hundreds.    From Wordnik.com.  [North Korea's Trail of Kidnapping and Terror] Reference

He was perfectly willing to keep his office staff late while he tracked down an unaccounted-for quarter missing from his change purse.    From Wordnik.com.  [The Business of America] Reference

With that strange, angry, and unaccounted-for mark still upon your shoulder, if only you knew what a fuss you were making over nothing.    From Wordnik.com.  [Leonie of the Jungle] Reference

If properly enforced, metering induces users to avoid wasting water, which may help reduce long-term costs or unaccounted-for water losses.    From Wordnik.com.  [Chapter 5] Reference