Simple Definition of improbable
: not probable : not likely to be true or to happen
Examples of improbable in a sentence
The team made an improbable comeback.
<it seems improbable that the two writers never met since they traveled in the same social circles>
Origin of improbable
Middle French or Latin; Middle French, from Latin improbabilis, from in- + probabilis probable
First Known Use: 1598
IMPROBABLE Defined for Kids
Definition of improbable for Students
: not likely : not probable <improbable stories>
Seen and Heard
What made you want to look up improbable? Please tell us where you read or heard it (including the quote, if possible).