What does unbelievable mean?
Unbelievable is an adjective used to describe something so extraordinary, surprising, or improbable that it strains credulity. In everyday speech it often conveys strong amazement or admiration: an unbelievable view, an unbelievable comeback, or simply “Unbelievable!” Depending on context, it can describe events that seem impossible, feats that seem extraordinary, and experiences that are difficult to process because of their intensity. The word is especially common in informal English, though it is fully accepted in ordinary writing and journalism when the reaction is emphatic rather than strictly technical. It is not a synonym for every use of “incredible”: “incredible” can mean extraordinary, excellent, or hard to believe, whereas “unbelievable” more strongly highlights the sense of being astonishing or beyond belief. The word’s force is rhetorical, so a speaker may use it hyperbolically. Its clear structure—negative “un-” plus “believable”—makes its meaning easy to remember and explains why it is so effective for expressing disbelief and amazement.
adjectiveSo improbable, extraordinary, or astonishing that one finds it difficult or impossible to believe. It can also express strong surprise, admiration, or amazement.
- So improbable, extraordinary, or astonishing that one finds it difficult or impossible to believe
- Used informally as an exclamation expressing strong surprise, amazement, or admiration
"The team produced an unbelievable comeback in the final minutes of the match."
"The view from the summit was absolutely unbelievable."
"It is unbelievable that the project was completed in only two weeks."
The word literally means “not believable,” yet its everyday job is to express just how astonishing something is.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Where does unbelievable come from?
English formed “unbelievable” by combining the negative prefix “un-” with “believable,” a compound that developed during the early modern period. “Believable” comes from “believe,” which ultimately derives from Latin credere, meaning “to believe” or “trust.” Related English words such as “belief,” “credible,” and “credit” reflect this same Latin root.
Related word forms
How unbelievable is actually used
The word is especially common in informal English and often conveys an emphatic personal reaction. It may be used hyperbolically, so it does not always mean that something is literally impossible.
Easily confused with unbelievable
“Unbelievable” is an adjective describing something astonishing or hard to believe, whereas “unbelieving” usually describes a person or reaction characterized by disbelief.