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.
OpenAI canceled the release of a new model, Astra 6.1, because it deemed the model unreliable and found that it frequently ignored instructions.
From Barron's ● Oct. 2, 2026
You have one friend who always pays you back and another who’s a little unreliable.
From MarketWatch ● Oct. 1, 2026
The most recent note focuses on energy, with Europe highly dependent on imports from increasingly unreliable sources and at relatively high prices.
From The Wall Street Journal ● Sep. 28, 2026
Large-scale water treatment technology remains known and used, but supply lines for chemicals and spare parts are unreliable.
From Science Daily ● Sep. 22, 2026
Are you familiar with the phrase unreliable narrator?
From "Confessions of a Murder Suspect" by James Patterson
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.
