Language doesn't have a Set of meanings because tokens, words, and (especially) phrases do not have rigorous definitions.  The token "is," word "To Be," has pages of definitions and sub-definitions in the OED.  Illustration:

x IS y ; Logical, where IS conveys "the same as"

The ball IS red  ; Phenomenological, where IS conveys "has the ontological accidental of"

In the Logical use the the use of the token within the term can be rigorously defined through axiomatics such that it can determined, necessarily, the relationship of x and y.

The the second use ... well, it gets complicated and the process gets more convoluted as one applies greater rigor.  Grossly, but accurately, simplified: the end point of analysis is ultimately achieved when the analyst declares, "Bugger this for a game of soldiers" and moves on.

Doublespeak happens when the communicator purposely manipulates the inherent ambiguity of Language for emotive (a la Logical Postivitism) persuasion with the intent to obfuscate, rather than illuminate.  

But what we are all coming to realise is that what people DO is more important than what they say.

That is why 'action' is a topic here at ET.

You can't be me, I'm taken