When sarcasm is mistakenly taken seriously, either the speaker is a lacking sarcasmist in the first sense of the word, or the listener and interpreter is lacking in the second (or, most often, both).
"Poe's Law kind of ruins it even for a skilled sarcasmist."
"Shes only jealous! Come on Destiny, lets go eat 4 pounds of ice cream, throw up, and then make out while pretending its not going to complicate our friendship!"
"Alright but this time I get to comfort your little brother when he walks in on us."
An adjective used to describe how someone says something, eg 'That was a sarcasimistic comment'. It is generally used by very intelligent people who need something more than sarcasm, sarcastic and all the other sarcas- words. These people should be treated with respect and worshipped.