Impossible

How to spell impossible

10 letters · 4 syllables

How to pronounce impossible

Say the part in capitals loudest.

What does impossible mean?

1. adjectiveNot able to happen, exist, or be done.

Impossible in a sentence

• Finishing the report by noon was simply impossible with so many interruptions.

• It is impossible to book a flight that cheap during the holidays.

Where does impossible come from?

Language of origin: Latin

This word descends from the Latin impossibilis, which simply joined the negative prefix in- (here softened to im- before the letter p, meaning 'not') to possibilis, meaning 'able to be done'. That second part was built on the verb posse, 'to be able', a contraction of the older potis esse, literally 'to be capable'. The same posse root gives us the everyday words 'possible', 'potent', and even 'power', so a whole family of capability words shares this ancestry. English took the word in during the 1300s by way of Old French, where it was already spelled with the doubled s, and that double s is exactly the spot writers second-guess today. Remembering that it is just 'possible' with 'im-' bolted on front keeps both the prefix and the -ible ending straight.

How the word is built

• im- (not)
• poss- (from posse: to be able)
• -ible (capable of)