Sanitise staggering do-or-die stance that lacks heart (9)
I believe the answer is:
deodorise
'sanitise' is the definition.
(deodorise can mean to clean a bad smell away)
'staggering do-or-die stance that lacks heart' is the wordplay.
'staggering' indicates anagramming the letters (letters stagger around).
'that lacks heart' means to remove the middle letters (I've seen 'lacking heart' mean this).
'stance' with its centre removed is 'se'.
'do'+'or'+'die'='doordie'
'doordie' with letters rearranged gives 'deodori'.
'deodori'+'se'='DEODORISE'
(Other definitions for deodorise that I've seen before include "Remove smell" , "Eliminate the smell" , "To remove stench" , "Get rid of smell" , "freshen up" .)