That cannot be apprehended; not apprehensible to or graspable by either body or mind.(adjective)
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Use "inapprehensible" in a sentence
"In the swirl of the Libby affair, one loses sight of the real offense, and it becomes almost inapprehensible what it is that Cheney/Libby/Rove got themselves into."
"The novelty of the avowal rendered what it carried with it inapprehensible by him in its entirety."
"He seemed to be passing through the universe of ideas like a comet — erratic, inapprehensible, untraceable."