interjection. used to express amusement or subtle surprise.interjection. Used to express doubt or confusion.interjection. Used to reinforce a question.interjection. this sense) (slang, with falling pitch) Used either to belittle the issuer of a statement/question, or sarcastically to indicate utter agreement, and that the statement being responded to is an extreme understatement. The intonation is changed to distinguish between the two meanings - implied dullness for belittlement, and feigned surprise for utter agreement.interjection. Used to indicate that one did not hear what was said.interjection. Used to create a tag question.