Spoiled (7)
'spoiled' is the definition.
('mar' can be a synonym of 'spoil')
This is all the clue.
(Other definitions for marred that I've seen before include "Damaged or spoiled" , "Blemished" , "'Impaired, spoilt (6)'" .)
'spoiled' is the definition.
(ruining is a kind of spoiling)
This is the entire clue.
(Other definitions for ruined that I've seen before include "Spoilt" , "Devastated" , "Completely destroyed" , "Reduced to a state of poverty" , "Bust" .)
'spoiled' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Another definition for soured that I've seen is " Made bitter like milk".)
'spoiled' is the definition.
(tainting is a kind of spoiling)
This is the entire clue.
(Other definitions for tainted that I've seen before include "Corrupted, sullied" , "Spoiled, stained" , "corrupt" , "I attend to spoiled condition" , "Contaminated, polluted" .)