It is *exactly* this that I am speaking against.
A word should be defined either by arbitrary authority, or by etymology, and ^not^ by common usage. By allowing words' meanings to change whenever the unwashed masses choose a new slang meaning, means that communication breaks down and becames nondeterministic and fully individualized: where what a person says is permitted to mean whatever the hearer wants it to, instead of communicating the speaker's thought clearly.
~CSL