Wiktionary
em dash
n. (context typography English) The symbol ('''—''') (gloss: used to demarcate a parenthetical thought or to indicate a break, or for emphasis)
Usage examples of "em dash".
He'd put it in his bottom desk drawer, along with the carbon of his story, to await a possible three-em add-a paragraph to be added to the Chronicler's account, under a three-em dash, at the last minute, should the actual indictment come through earlier than expected.
Hed put it in his bottom desk drawer, along with the carbon of his story, to await a possible three-em adda paragraph to be added to the Chroniclers account, under a three-em dash, at the last minute, should the actual indictment come through earlier than expected.