Semantical nonsense arises when it is impossible to indicate what it is that one is talking about.
The semantical paradoxes arise from this impossibility. The statement of the 'Liar paradox', for example, predicates falsity of itself but since this state- ment is nothing other than the predication of falsity, we never find out what statement we are claiming to be false. Boyle goes on to say that this is not the way performative incon- sistency works. The reason given by Boyle for the nature of the semantical paradoxes is a bit opaque. I think it's a bit simpler than a case of a meaning or of a referent chasing its own tail, so to speak.