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Synonyms

unaccounted-for

American  
[uhn-uh-koun-tid-fawr] / ˌʌn əˈkaʊn tɪdˌfɔr /

adjective

  1. not accounted for; not understood; unexplained.

    an explosion resulting from some unaccounted-for mechanical failure.

Etymology

Origin of unaccounted-for

1790–1800; formed on the verb phrase account for; un- 1, -ed 2

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

The authors also noted that other, unaccounted-for health or lifestyle factors may have influenced the results.

From Science Daily • Oct. 27, 2025

But it later confirmed there was another unaccounted-for passenger on the flight.

From BBC • Aug. 10, 2024

Relatives of passengers still listed as unaccounted-for waited outside a hospital for news, among them Mirella Ruci, whose 22-year-old son Denis remains missing.

From Seattle Times • Mar. 3, 2023

Worse, the GAO reports that the $220 billion in unaccounted-for equipment and parts is "likely significantly understated."

From Salon • Feb. 15, 2023

Gies & Co. still had some unaccounted-for thousand-guilder bills, which they used to pay their estimated taxes for the coming years, so everything seems to be aboveboard.

From "The Diary of a Young Girl" by Anne Frank

Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.