Wept and sang like a moderate soprano, perhaps in the absence of war (4)
I believe the answer is:
bled
'wept' is the definition.
'sang like a moderate soprano perhaps in the absence of war' is the wordplay.
'sang like a moderate soprano perhaps' becomes 'warbled' (warble can mean to sing in a high voice).
'in the absence of' indicates named letters should be taken away.
'warbled' with 'war' removed is 'BLED'.
'and' acts as a link.
(Other definitions for bled that I've seen before include "Showed effects of injury" , "Extracted blood as treatment" , "Haemorrhaged" , "Seeped (into an adjoining colour)" , "Lost blood" .)