+0
The word "crack", in its relation to drug use/abuse, was once seen as slang and used only among certain people, but now, many people know and use the word to refer to the same thing. Could we now say that the word is standard, or would you still see it as slang - or could it be both slang and standard at the same time? Also, has there ever been a time in the history of the English language where there was/has been a clear division between standard and non-standard use or is the acceptance of what is or isn't standard a more personal thing?
+0
.
I rely on the lexicographers myself. Some label it as slang and others do not:

33. Also called rock. Slang. pellet-size pieces of highly purified cocaine, prepared with other ingredients for smoking, and known to be especially potent and addicting.

9. Slang Crack cocaine.

9: a potent form of cocaine that is obtained by treating the hydrochloride of cocaine with sodium bicarbonate to create small chips used illicitly for smoking —called also crack cocaine

7 (also crack cocaine) a potent hard crystalline form of cocaine broken into small pieces.

crack (DRUG) noun [ U ] SLANG a pure and powerful form of the drug cocaine


The Online Etymology Dictionary attests the word only from 1985.
.
Comments  
I rely on the lexicographers myself. Some label it as slang and others do not:

If some do one thing, and others another, which lexicographers do you rely on?