unreliable
Americanadjective
adjective
Other Word Forms
Etymology
Origin of unreliable
Explanation
Someone unreliable can't be trusted to do something. Things can be unreliable too, like a bike with a wobbly wheel. The word "rely" is a clue to what unreliable means. When you can rely on something, you can count in it — it's reliable. On the other hand, you'd better not count on an unreliable person. People can be unreliable because they're dishonest, always late, bad at their job, or just inconsistent. Things can be unreliable because they're broken or old. A train schedule can be unreliable if the trains are never on time. Unfortunately, there's a lot of stuff in life that's unreliable, so be careful.
Vocabulary lists containing unreliable
STAAR English I: Elements of Literature
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STAAR English II: Elements of Literature 1
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Point of View
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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.
They say the case was built on the testimony of unreliable witnesses, some of whom have given statements against him only for them to be later recanted in court.
From BBC ● Sep. 18, 2026
In his closing argument, defense attorney Brian Steel painted Hester, Jones and Grant as unreliable “snitches, cooperators, rats” seeking to secure a lighter sentence by implicating Banks.
From Los Angeles Times ● Sep. 12, 2026
That does not mean clocks suddenly become unreliable.
From Science Daily ● Sep. 11, 2026
Health trackers might spit out unreliable numbers, but doctors say they’re still useful for spotting personal trends.
From The Wall Street Journal ● Sep. 7, 2026
Human beings, Montaigne argued, are imperfect, and so human knowledge is necessarily unreliable.
From "The Invention of Science" by David Wootton
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.
