It makes sense because dead cats have a lot of physical properties. Squishiness, odor, all that. Elasticity, probably. I haven't been able to find any research demonstrating that last one, and the people at the SPCA won't even take my calls anymore, but it seems reasonable. From a great enough height, a dead cat would probably bounce a bit. I haven't tested this theory myself, but I could see where the phrase could be relatable to such a predatory, life-crushing system like the stock market.

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"Wow. That one was like 8 inches, at least."

And if you don't find it too disgusting, there's no reason not to apply the same thinking to anything that displays a late, probably doomed comeback. Your battered football team scores a third-quarter touchdown and is now down by only 16? Dead cat bounce. A fading celebrity stars in a low-budget indie movie that isn't terrible? Dead cat bounce. Your patching up a misguided relationship with someone who's clearly wrong for you? Dead cat bounce.

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"Here's what I think of your cat, and here's what I think of YOU, Karen!"

The turtle doesn't belong there, clearly didn't get there on his own, and is completely stuck unless you help it down. So the phrase is commonly used to describe politicians, implying they've been put into a job they have no business being in and are utterly helpless while there. You can go ahead and apply it to any politician you don't like. Go ahead. I'll wait.

Felt good, didn't it? Insults always make you feel like a bigger person. And there's no reason to stop with politicians! The concept of a post turtle can be applied to many people, especially in the workplace. I bet some of your bosses or co-workers have been post turtles, haven't they? Hell, you might be one yourself.

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"Dang."

A baseball is a good example: the basic scientific calculations that describe acceleration and force are pretty straightforward, high school-level stuff. But even these can get pretty complicated when we have to consider friction or air resistance, or objects of an unusual shape. When students are just learning these calculations, they're often instructed to ignore friction or air resistance or, if not, to assume objects have a uniform shape. Enter the spherical cow.

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"WE SHOULD NOT BE."

The spherical cow might show up in a problem about projectile cows or buoyant cows or something like that. And sure that sounds ridiculous, and then a bit more so when you start to consider the sounds they'd make rolling down a hill while a farmer angrily throws his hat in the dirt, but these simplifying assumptions can be useful. Even expert scientists, with black belts and long, wispy beards, will use gross oversimplifications like this to quickly hone in on an approximate answer, which is sometimes good enough for their purposes. And if not, these crude approximations can still be useful for guiding the way for further, more detailed research.

That should stop them from rolling away, at least.

"Weasel words" describe a type of language people sometimes use to confuse or obfuscate what they're actually saying, so named because of the weasel's reputation for duplicity. Weasel words can make weak statements sound stronger, strong statements sound weaker, or conceal who is making the statement. They usually take the form of vague attributions like "experts say" or "it is said that" to conceal that there is no actual source for the statement or that the author is trying to hide the fact that they're the one making that statement. Another common tactic is to use "probably" or "occasionally" to weaken an overly bold claim.

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"Odd that I've not seen these experts that say 'Bush did 9/11.' They must be pretty elusive."

Weasel words are a big challenge on Wikipedia for obvious reasons, but their use is widespread across the entire Internet. It pains me to admit, but experts are pretty certain that I have myself used weasel words quite a bit in my writing. All those columns slandering Ted Danson, for example.

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"If Cracked says Ted Danson is probably the Zodiac Killer, that's all I need."