QUESTION MARK, also especially AmE interrogation mark, interrogation point. The PUNCTUATION mark (?). Its primary use is to show that a preceding word, phrase, or sentence is a direct QUESTION: Do you want more to eat? It is not used in indirect speech, because a reported question is part of a statement: I asked you whether you wanted more to eat. The question mark is sometimes repeated in informal usage or followed by an exclamation mark/point in order to indicate a specially strong question (What did you say??; What did you say?!). It is also used, often in brackets, to express doubt or uncertainty about a word or phrase that immediately follows or precedes it: Julius Caesar, born (?) 100 bc; They were then seen leaving the house (in tears?) and walking away.

ques·tion mark • n. a punctuation mark (?) indicating a question. ∎ fig. used to express doubt or uncertainty about something: there's a question mark over his future.