sarcasm

As a noun sarcasm

is (uncountable) a sharp form of humor, intended to hurt, that is marked by mocking with irony, sometimes conveyed in speech with vocal over-emphasis insincerely saying something which is the opposite of one's intended meaning, often to emphasize how unbelievable or unlikely it sounds if taken literally, thereby illustrating the obvious nature of one's intended meaning.

As a verb sarcase is

(nonstandard) to use sarcasm.