Not standing for being dishonest (5)
I believe the answer is:
lying
I believe this is a double definition.
'not standing' is the first definition.
('lie' is the opposite to 'stand')
'being dishonest' is the second definition.
(synonyms)
'for' acts as a link.
(Other definitions for lying that I've seen before include "Telling fibs" , "Not being disturbed" , "Perjury" , "Untruthful - in bed?" , "Saying what is 23" .)