while reading wikipedia (internet nerd) about the differences between hyphens and dashes (grammar nerd) i read this example (sci-fi nerd): It can be used instead of an ellipsis to indicate aposiopesis, the rhetorical device by which a sentence is stopped short not because of interruption but because the speaker is too emotional to continue, such as Darth Vader’s line “I sense something; a presence I have not felt since—” in Star Wars Episode IV: A New Hope.