inconceivable

inconceivable folly; an inconceivable disaster.

they behaved with inconceivable cruelty.

an inconceivable victory against all odds.

Colour is inconceivable to people born blind.

It is inconceivable that a thing can both be and not be.

He can't go on holiday alone; it's inconceivable.

This sort of work would have been inconceivable before the advent of microprocessors.

It once seemed inconceivable to everyone that men should travel to the moon.

The thought of leaving her family was inconceivable to her.

It's almost inconceivable that a handicapped girl is very independent and lives all alone.