Security giving the all clear to work? (10)
I believe the answer is:
collateral
'security' is the definition.
(collateral is a kind of security)
'the all clear to work?' is the wordplay.
'work?' indicates an anagram (I've seen 'work' mean this).
'all'+'clear'+'to'='allclearto'
'allclearto' anagrammed gives 'COLLATERAL'.
'giving' is the link.
(Other definitions for collateral that I've seen before include "Aside from the main issue" , "Something pledged as security for a loan" , "Money put up" , "damage?" , "Confirmatory - recall a lot (anag)" .)