Snub some who malign or execrate (6)
I believe the answer is:
ignore
'snub' is the definition.
('ignore' can be a synonym of 'snub')
'some who malign or execrate' is the wordplay.
'some' indicates a hidden word (some of the parts of the word are used).
'IGNORE' is hidden in the letters of 'who malign or execrate'.
(Other definitions for ignore that I've seen before include "Send to Coventry" , "Discount" , "Fail to observe" , "Intentionally disregard" , "Deliberately disregard" .)