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I'm looking for a word that conveys something is "not understandable". For instance:
The message was staticky and corrupted, making it not understandable.
"Not understandable" sounds strange and like a double negative. I'm looking for a single word to take the place.
Some results suggest "bizarre" and "alien", but that's not what I'm going for. The speaker knows what it is, but can't understand it.