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.
According to the complaint, Prabhakar had taught the story for nearly a decade without incident and used it in a unit on unsympathetic and unreliable narrators alongside works by Ernest Hemingway and Raymond Carver.
From Salon ● Aug. 2, 2026
But even with unreliable rule of law and excessive regulation, the overwhelming path to success is through developing excellent products and satisfying customers.
From The Wall Street Journal ● Jul. 28, 2026
But, as the relationship progressed, Griffiths became more and more unreliable - often cancelling plans at the last minute.
From BBC ● Jul. 15, 2026
You could patch up the car, which could make it an unreliable jalopy that breaks down — leading to you having to pour more money into fixing it.
From MarketWatch ● Jul. 13, 2026
By then, my mother had acquired a motor-boat, a small and not very seaworthy white wooden vessel which sat far too low in the water and was powered by an unreliable one-cylinder engine.
From "Boy: Tales of a Childhood" by Roald Dahl
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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.