unreliable

adjective

un·​re·​li·​able ˌən-ri-ˈlī-ə-bəl 

: not reliable : undependable, untrustworthy

an unreliable friend

an unreliable source of funding

an unreliable car

unreliability

ˌən-ri-ˌlī-ə-ˈbi-lə-tē 

noun

the unreliability of the data

a person with a reputation for unreliability

unreliably

ˌən-ri-ˈlī-ə-blē 

adverb

a method that works unreliably

Examples of unreliable in a Sentence

Recent Examples on the Web

In my view, deal flow is now an unreliable proxy for value creation. — Peter Doyle, Forbes.com, 26 June 2026

At a time when global supply chains are highly unreliable, Australian researchers are working to de-risk supply chains for startups and industries in the future through domestic capacity building. — Ameya Paleja, Interesting Engineering, 25 June 2026

My lab and others around the world are developing these alternatives as backup for when GPS is unavailable or unreliable. — Zak Kassas, The Conversation, 23 June 2026

Elders still literally freeze in winter because energy is unreliable or unaffordable. — Cody Two Bears, Rolling Stone, 17 June 2026

Word History

First Known Use

1810, in the meaning defined above

Rhymes for unreliable

• liable
• pliable
• triable
• viable
• classifiable
• justifiable
• modifiable
• notifiable
• satisfiable
• specifiable
• undeniable
• verifiable