improbable

Your parents might tell you it's improbable that they'll buy you a car when you turn 16. Since improbable means something is unlikely but not impossible, your optimism allows you to keep hoping.

The adjective improbable also means statistically unlikely to happen. You might be afraid to fly, but the odds of a plane crash are so low that such an event is improbable. Improbable also means something that is so outrageous that you'd never admit you believed in it. You know the existence of the Loch Ness Monster is improbable, but that doesn't stop you from looking for it when you travel to Scotland.

Definitions of improbable
1

adj having a probability too low to inspire belief

Synonyms:
unbelievable, unconvincing, unlikely
implausible
having a quality that provokes disbelief

adj too improbable to admit of belief

Synonyms:
marvellous, marvelous, tall
incredible, unbelievable
beyond belief or understanding

adj not likely to be true or to occur or to have occurred

“an improbable event”
Synonyms:
unlikely
supposed
mistakenly believed
Antonyms:
likely, probable
likely but not certain to be or become true or real
equiprobable
equally probable
presumptive
having a reasonable basis for belief or acceptance
verisimilar
appearing to be true or real
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