The first thing that comes to my mind is one of these: - (ie a type of hyphen). However, only context will tell us if we have the correct definition of the word.
As a writer cum editor, I too think em-dash and en-dash (— and –, respectively).
My next thought is a short sprint, like the 100m dash.
My next thought is a hasty departure. Sorry, guys, I have to dash now.