The OED defines “nonsense” as: that which is not sense; words which make no sense or convey absurd ideas…unsubstantial or worthless stuff or things.
We prefer the Dada definition:
Nonsense: a creature from the unconscious that surrounds, underlies and fills all that isn’t commonly understood….
Serious nonsense comes from great depth like clear springs. In the upper layers of blah-blah everything makes sense, unfortunately, and the din sucks all the oxygen.
Andrei Codrescu, The Posthuman Dada Guide (Princeton University Press 2009) p. 200
You’d have to say, though, that in the upper layers of blahblah these days (management- speak, politics-speak) nothing makes any sense. It’s like a mat of weeds that covers a lake. But the pure springs of nonsense bubble on, fresh and exhilarating.