That's the colloquial term for them in Shaun's world, though technically they're the dead or the undead or the infected. Shaun doesn't keep track of what the current official scientific term is -- that's George's department, cut and dry facts.

He does take note of walkers, considers asking if these guys are swimmers, but instead opts for less dumb jokes and more serious answer to the question.

"All the ones I've seen so far aren't fresh, definitely not newly amplified, so I don't think it's an outbreak. ...yet. They're all pretty soggy, so I'm guessing the lake. The folks at the museum said something about the lake being a dumping ground for mob hits, which I'd figured was an urban legend." He shrugs with a sheepish sort of grin. "Maybe it was true after all."