adj B2 Upper-Intermediate Uncommon

unreliable

uhn-rih-LEYE-uh-bl

Unreliable (adj) means not able to be trusted or depended on to perform consistently. Example: “His old car was unreliable and kept breaking down.”

adj

Not able to be trusted or depended on to perform consistently.

"His old car was unreliable and kept breaking down."

"The witness was considered unreliable by the jury."

How to use unreliable

Learner’s notes

In plain EnglishNot consistently trustworthy or dependable — used for people, sources, or equipment.

Common pairings

unreliable source unreliable narrator notoriously unreliable

Word forms

more unreliable comparative, unreliables plural, most unreliable superlative

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Fill the gap

Can you complete this real example?

His old car was _____ and kept breaking down.

Etymology

From un- ("not") plus reliable.

Synonyms

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undependable

Rhymes for unreliable

able fable cable table viable liable stable tenable parable affable amiable notable

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Frequently asked questions

What does “unreliable” mean?

The word “unreliable” means not able to be trusted or depended on to perform consistently. In plain terms, not consistently trustworthy or dependable — used for people, sources, or equipment.

How do you pronounce “unreliable”?

“Unreliable” is pronounced uhn-rih-LEYE-uh-bl (/ˌʌn.ɹəˈlaɪ.ə.bəl/ in IPA).

How do you use “unreliable” in a sentence?

Here is “unreliable” used in a sentence: “His old car was unreliable and kept breaking down.”

What part of speech is “unreliable”?

“Unreliable” is an adjective.

Is “unreliable” a common word?

“Unreliable” is an uncommon word in modern English, usually learned at around the B2 level.

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