Seek food when enemy overtakes tabloid (6)
I believe the answer is:
forage
'seek food' is the definition.
(I've seen this in another clue)
'enemy overtakes tabloid' is the wordplay.
'enemy' becomes 'foe' (synonyms).
'overtakes' is an insertion indicator.
'tabloid' becomes 'rag' (informal term for a tabloid newspaper).
'foe' enclosing 'rag' is 'FORAGE'.
'when' acts as a link.
(Other definitions for forage that I've seen before include "Seek for food" , "Collect food" , "Hunt for food or provisions" , "Plunder; rummage" , "Wander and feed" .)