i think a middle-school english teacher broke my brain by saying you can't define irony except by example and so any subsidiary definition that depends on a definition of irony is also going to import it; that said women on dating sites regularly refer to themselves as sarcastic
The use of words expressing something other than their literal intention! Now THAT... IS... irony!"
— Bender, Futurama
It’s not hard at a linguistic level, only at a philosophical level