As Steve Martin put it, “Let’s face it: some people have a way with words, and other people… oh, ah… not have way, I guess.”
Cacology looks like it could mean ‘talking shit’ – you know, caca plus -logy. But this is caco, as in cacophony, from Greek κακός; it means ‘bad’.
Of course, that could still mean talking bad about someone – you know, vilipending them, as the kids say, or, yes, talking shit, as professors say (well, the ones I know, anyway). And back in the 1600s, that’s what cacology meant. But that sense has fallen into desuetude, and now, when this word is used, it’s used to mean ‘talking badly’.
Which can still mean a number of things. It could mean talking wildly and crazily –
– or articulating insufficiently –
– or, even if speaking (or singing) smoothly and clearly, still incomprehensibly –
– but it can also mean just, as the Oxford English Dictionary puts it, “Bad speaking, bad choice of words; vicious pronunciation.” (Does that sound like a reprimand to a talking dog?)
Opinions vary widely on what is “bad,” of course. Some people cannot abide the word get in any circumstance; some promote superstitions such as that you should not end a sentence with a preposition; some believe that “[person] and me” is always an error for “[person] and I.” On the other hand, some dislikes have some basis in fact and established usage. Think people most this that sentence grammar correct not has, and as long as we’re following the established rules of any variety of English I’ve ever seen, they’re right. But blenderized syntax is uncommon. Tired clichés, needless circumlocutions, other obfuscations, and dime-machine buzzwords, all quite common in usage, are also disliked with good cause.
And of course so are vicious words – racial epithets, for instance.
And, for that matter, swearwords, cusswords, naughty words – whatever you want to call them. I’m not at all opposed to swearwords; they serve a necessary function, and they do not bespeak poor character or intelligence (oh, believe you me: some of the nicest and best-educated people I know use cusswords freely as the occasion demands, and some of the worst people I’ve ever met would never utter an impure word – though there are plenty of very nice people who don’t swear, too, and no shortage of nasty people who do). But I do think they need to be seen as cacology, or else they lose their charge. After all, talking shit is less effective if the shit is just… caca.