It was worse than dead; his brain was gone.
There are a lot of ways to die if you're a red shirt. You can be shot by a poisonous plant, step on an exploding rock, be struck by lightning, get whacked by a native with a big stick, choke on a dikironium cloud, or, our personal favorite, be beamed down to a planet that's not actually there and get sucked into space, never to be seen again. But it's an entirely different matter when Bones says, "He's undead, Jim." That's way worse than dead, and the entire galaxy could be at risk! Be sure to double tap with your phaser.
Fun factoid: The very first "He's dead, Jim" referred to a dog that had an unfortunate encounter with a transporter. Yeah. You knew that. But what is it with us using dogs for space experimentation? They may be "man's best friend," but, if actions speak louder than words, the feeling's not so much mutual. (Don't worry. We won't be sending any of our puppies into space, fictional or otherwise.)
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