[blue]The snag here is that most of those categories are defined as not coming under a rule , i.e. they are only negatively defined (by exclusion), e.g. "non-standard"
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Yeah, but...
a buzz word is very different than slang.
(once in a while, maybe you could say they over lap--bling-bling, maybe for a while was both.

i haven't looked up specific dictionary entries for slang, vs. idiolect--but idiolect is (to me, to my way of thinking) something more like how londoner's say th (as in thread or other words) not really slang. Idiolect might also includes words like bleeper (vs US beeper) or skip(vs dumpster) or to put a finer point on it, it might be the difference between (US,North) setting a table and (US South) laying a table.
Set and Lay are not cant, or slang, but diolect differences.

my other obsession