Is The Interrobang Grammatically Correct?

An interrobang is a non-standard punctuation mark that is used to indicate a statement that contains both a question and an exclamation at the same time. The term interrobang, which was previously spelt as interabang, is derived from the combination of the interrogative or question mark and the bang, which is printers' slang for the exclamation point. Originally spelled as interabang.