Lied about head’s inaction (8)
I believe the answer is:
idleness
'inaction' is the definition.
(I've seen this before)
'lied about head's' is the wordplay.
'about' indicates anagramming the letters.
'head' becomes 'ness' (type of geographical point).
'lied' with letters rearranged gives 'idle'.
'idle'+'ness'='IDLENESS'
(Other definitions for idleness that I've seen before include "I'm having nothing to do" , "not working" , "Lazy behaviour" , "Sloth - there may be love in it" , "State of doing nothing" .)