An exclamation point or exclamation mark ( ! ) is a punctuation mark commonly used to express strong, intense emotions in declarations. It can also be used to add emphasis to interjections and commands.
1. (Grammar) the punctuation mark ! used after exclamations and vehement commands
2. (Printing, Lithography & Bookbinding) this mark used for any other purpose, as to draw attention to an obvious mistake, in road warning signs, (in chess commentaries) beside the notation of a move considered a good one, (in mathematics) as a symbol of the factorial function, or (in logic) occurring with an existential quantifier