The idea that two die-hard enemies who will never ever make up could suddenly become best friends is an example of something that is inconceivable.
- Impossible to comprehend or grasp fully: inconceivable folly; an inconceivable disaster.
- So unlikely or surprising as to have been thought impossible; unbelievable: an inconceivable victory against all odds.
- in′con·ceiv′a·bil′i·ty, in′con·ceiv′a·ble·ness
(comparative more inconceivable, superlative most inconceivable)