impossible

adjective

im·​pos·​si·​ble (ˌ)im-ˈpä-sə-bəl 

1

a

: incapable of being or of occurring

b

: felt to be incapable of being done, attained, or fulfilled : insuperably difficult

an impossible deadline

2

a

: extremely undesirable : unacceptable

b

: extremely awkward or difficult to deal with

the actor was impossible on the set

impossibleness noun

Synonyms

• unlikely
• hopeless
• problematical
• problematic
• impractical
• futile

Examples of impossible in a Sentence

It's impossible to predict the future.

The heavy rain made it impossible to see the road.

It's physically impossible for a child to lift that much at once.

It's virtually impossible to book a flight just before the holiday.

These math problems are impossible!

You refuse to help and then criticize me for not doing it right? You're impossible!

My boss is just an impossible woman.

Recent Examples on the Web

Then, the shirt with long sleeves and the four-fingered corn hands; and finally, the top ear-of-corn itself, bulbous and high and impossible get into without assistance (at least for me!). —Teri Sforza, Oc Register, 1 Aug. 2025

Moore had a fluidity and grace and could move in a way that seemed impossible. —Sabreena Merchant, New York Times, 1 Aug. 2025

Trying to book time on your European colleagues in the month of August is nearly impossible! —Scott Hutcheson, Forbes.com, 1 Aug. 2025

Throughout her hospital stay, walking was nearly impossible. —Ashley Vega, People.com, 1 Aug. 2025

Word History

Etymology

Middle English, from Anglo-French & Latin; Anglo-French, from Latin impossibilis, from in- + possibilis possible

First Known Use

14th century, in the meaning defined at sense 1a

Phrases Containing impossible

• the impossible

Rhymes for impossible

• possible

Kids Definition

impossible

adjective

im·​pos·​si·​ble (ˈ)im-ˈpäs-ə-bəl 

1

a

: incapable of being or of occurring

b

: very difficult : hopeless

an impossible situation

2

: very bad or unpleasant

an impossible person

impossibly

-blē

adverb

Legal Definition

impossible

adjective

im·​pos·​si·​ble

: not possible : incapable of being done, attained, or fulfilled

a party's performance is impossible in part