Lift most of the secrecy (7)
I believe the answer is:
stealth
'secrecy' is the definition.
(I've seen this in another clue)
'lift most of the' is the wordplay.
'lift' becomes 'steal' (I've seen this before).
'most of' means to remove the last letter.
'the' with its last letter removed is 'th'.
'steal'+'th'='STEALTH'
(Other definitions for stealth that I've seen before include "The last (anag.)" , "Secretiveness, furtiveness" , "Unseen machination" , "Cautious and surreptitious action or movement" , "quality needed by cat burglars" .)