POT as a "standard"

[RonButters at AOL.COM]

In a message dated 7/1/02 3:56:00 PM, dave at WILTON.NET writes:

<< Based on this, I stand by my statement that "pot" has made or is making its
way into standard American English, while "grass" remains a slang term. >>

Interesting data. But it seems to me that all this merely demonstrates that
MARIJUANA is the standard term and POT and GRASS are slang terms of varying
quantities of use and levels of informality; though both are widely known and
used, POT is more frequent and is to some degree the preferred informal term.

Just what does it mean to say that a word "is making its way into standard
American English"?