We have a whole set of colloquial words for distasteful, disreputable, insalubrious things that you would generally shy away from or eschew outright: scuzzy, sleazy, sketchy, skeezy, skanky, scurvy, skeevy…
You can notice some commonalities, and you would not be off base to suspect some cross-influence. Usage of words can be influenced by the senses of other words they sound like, and if we make up a new word – especially one meant to be particularly vivid – we tend to draw on established sound patterns from other words of similar sense (I covered this in my master’s thesis, if you’d like some substantiation for it).
But of course there are some words that established the pattern and others that followed it. We can feel confident that scurvy, for instance, was an early entrant in this group; it showed up in its present form in the 1500s, and it traces (by way of scurf) back to Old English. Sleazy has been with us since the 1600s, though its origins are sketchy (while sketchy is more recent, but its origins aren’t sleazy).
And how about skeevy? That seems like a portmanteau, doesn’t it, or at least a phonaesthematic confection? It’s not. It showed up in English quite recently, apparently the 1970s, but its origins are, in their way, ancient and clear: it comes from an Italian word, schifo, ‘loathing’ or ‘crap’ (and its related verb, schifare, ‘loathe’). For those who don’t know, sch in Italian is pronounced like “sk.” And while the f is “f” in standard Italian, it can be voiced to “v” in regional varieties – such as the variety spoken in South Philadelphia, where skeevy appears to have entered English (this is the kind of Italian where prosciutto is said like “brazhoot” and capicola like “gabagool”).
And where does schifo come from? Not from Latin! Rather, Italian seems to have gotten it via Old French from Frankish, which in turn took it from Proto-Germanic *skeuhaz… which is also the source of English shy and eschew.
So skeevy just happened to sound appropriate when it was imported (in modified form) into English. But of course it might not have been imported if it had not sounded suitable! Now, if you’re looking for a word made up on the basis of just sounding right, try skeezy, which showed up in the early 1990s, evidently on the model of skeevy, sleazy, and the rest.
And what are the subtle shades of meaning between all these words? You know, that would probably make a good journal article… if not a whole dissertation. But if you have a sense of differences in how you would use them, don’t be shy, tell me; I love good usage data points.