Improbable

How to spell improbable

10 letters · 4 syllables

How to pronounce improbable

Say the part in capitals loudest.

What does improbable mean?

1. adjectiveNot likely to be true or to happen.

Improbable in a sentence

• An upset of that scale seemed highly improbable before the match.

• The witness gave an improbable account that no one could verify.

Where does improbable come from?

Language of origin: Latin

This word comes from the Latin improbabilis, formed from the negative prefix in- (which softens to im- before the letter b, meaning 'not') joined to probabilis, meaning 'provable' or 'credible'. That root traces back to the verb probare, 'to prove, test, or approve', which itself grew from probus, meaning 'good, honest, or upright'. English picked the word up in the sixteenth century, partly through French, with the sense of something so unlikely it could scarcely be proven true. The same probare root still lives in everyday English words such as 'probe', 'prove', 'probable', and 'approve', all of them carrying the old idea of testing whether something holds up. Remembering that the middle is the 'prob' of 'probable', simply with 'im-' in front, keeps the spelling steady.

How the word is built

• im- (not)
• prob- (from probare: to prove or test)
• -able (capable of)