Saint corrupted Magi? Shame! (6)
I believe the answer is:
stigma
'shame' is the definition.
(stigma can mean shame or disgrace)
'saint corrupted magi?' is the wordplay.
'saint' becomes 'st' (abbreviation).
'corrupted' indicates anagramming the letters.
'magi' anagrammed gives 'igma'.
'st'+'igma'='STIGMA'
(Other definitions for stigma that I've seen before include "Part of a flower" , "Disgraceful mark" , "Brand or mark of infamy" , "Badge of shame" , "part of plant" .)