Revolting pants suggested by Bertha? (3,6)

I believe the answer is:

bad breath

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'revolting' is the definition.
I don't know anything about this answer so I cannot tell whether it can be defined by this definition.

'pants suggested by bertha?' is the wordplay.
'pants' becomes 'bad' (British slang - it was pants).
'suggested by bertha?' becomes 'breath' (I can't justify this - if you can you should believe this answer much more).
'bad'+'breath'='BAD BREATH'

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I've seen this clue in The Sun.

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