Lifeless? Very! (4)
I believe the answer is:
dead
This clue is a double definition.
'lifeless?' is the first definition.
(similar in meaning)
'very' is the second definition.
(dead can mean very or absolutely, eg 'dead wrong')
(Other definitions for dead that I've seen before include "Six feet under" , "Exhausted -- layabout" , "cold" , "Pushing up the daisies" , "Stiff - bereft of life" .)