Thrash something and run off (4,2)
I believe the answer is:
beat it
'run off' is the definition.
I don't know anything about this answer so I cannot judge whether this works.
'thrash something' is the wordplay.
'thrash' becomes 'beat' (synonyms).
'something' becomes 'it' (I've seen this in other clues).
'beat'+'it'='BEAT IT'
'and' is the link.
Can you help me to learn more?
(Other definitions for beat it that I've seen before include "leave" , "Sling your hook!" , "fly away" , "Scarper" , "make off furtively" .)