Definition of unthinkable
1
: not capable of being grasped by the mind
2
: being contrary to what is reasonable, desirable, or probable : being out of the question
Test Your Vocabulary
Eponyms: Words Named After People
-
- What is the best definition of boycott?

Test your knowledge - and maybe learn something along the way.
TAKE THE QUIZ
A daily challenge for crossword fanatics.
TAKE THE QUIZLove words? Need even more definitions?
Merriam-Webster unabridged
Share unthinkable
Time Traveler for unthinkable
The first known use of unthinkable was in the 15th century
See more words from the same century