Sly-looking chap (7,3)

I believe the answer is:

peeping tom

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'sly-looking chap' is the definition.
I can't judge whether this definition defines the answer.

'looking chap' is the wordplay.
'looking' becomes 'peeping' (peeping is a kind of looking).
'chap' becomes 'tom' (a man's name).
'peeping'+'tom'='PEEPING TOM'

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(Other definitions for peeping tom that I've seen before include "Spy" , "Voyeur" , "who likes looking at females" , "One who spies pruriently on others" .)

I've seen this clue in The Globe and Mail.

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