Put out of action on account of dreadfully bad lies (7)
I believe the answer is:
disable
'put out of action' is the definition.
(I've seen this before)
'dreadfully bad lies' is the wordplay.
'dreadfully' indicates anagramming the letters.
'bad'+'lies'='badlies'
'badlies' is an anagram of 'DISABLE'.
'on account of' is the link.
(Other definitions for disable that I've seen before include "Weaken" , "Deactivate" , "Put out of action" , "Incapacitate" , "For hamstring" .)