Run carelessly after slap (4)
I believe the answer is:
dash
'run carelessly' is the definition.
I cannot understand how the remainder of the clue works.
Can you help me to learn more?
(Other definitions for dash that I've seen before include "- - ; panache" , "Stroke < > to frustrate" , "quite mild oath" , "Run hurriedly; hyphen" , "hasty journey" .)