Meaning & use
unreliable
Last updated
UK/ˌʌnrɪˈlaɪəbl/
US/ˌʌnrɪˈlaɪəbl/
Meaning
adjectivecomparable
Not able to be depended on, because it or they often fail, change or turn out wrong.
Grammar: Before a noun or after be: an unreliable car; the car is unreliable.
Patterns
- unreliable source
- unreliable witness
The bus service is unreliable in winter.
He is an unreliable friend and often forgets plans.
Old forecasts are unreliable.
Word forms
| comparative | more unreliable |
|---|---|
| superlative | most unreliable |
Common combinations
- unreliable source
- The rumor came from an unreliable source.
- notoriously unreliable
- The old car is notoriously unreliable.
- unreliable witness
- The lawyer called him an unreliable witness.
- unreliable narrator
- The novel has an unreliable narrator.
Synonyms and how they differ
- undependable
- Nearly the same but rarer.
- fickle
- Describes people who change their mind, not things that fail.
- flaky
- Informal, often about people who cancel plans.
Opposites
Word family
- reliable adjective
- able to be trusted
- unreliability noun
- lack of dependability
- unreliably adverb
- in an unreliable way
Practice
I stopped using that website because its information was ___.
Choose one answer.
Information that cannot be trusted is unreliable. The other words describe other problems.
Make it your own
Write a sentence using “unreliable”, then check it and compare it with the examples above.
Your sentence stays on this page and is not sent anywhere.