WordReference Random House Unabridged Dictionary of American English © 2025
un•con•ceiv•a•ble
(un′kən sē′və bəl),USA pronunciation adj. [Archaic.]
un′con•ceiv′a•ble•ness, n.
un′con•ceiv′a•bly, adv.
- inconceivable.
- un-1 + conceivable 1605–15
un′con•ceiv′a•bly, adv.