Terrible costumes for vices (3,6)

I believe the answer is:

bad habits

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'vices' is the definition.
I know nothing about this answer so I cannot judge whether this works.

'terrible costumes' is the wordplay.
'terrible' becomes 'bad' (similar in meaning).
'costumes' becomes 'habits' (I am not sure about this - if you are sure you should believe this answer much more).
'bad'+'habits'='BAD HABITS'

'for' acts as a link.

Can you help me to learn more?

I've seen this clue in The Mirror.

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