Sadly, icon is man who cannot sleep (9)

I believe the answer is:

insomniac

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'cannot sleep' is the definition.
I can't tell whether this defines the answer.

'sadly icon is man' is the wordplay.
'sadly' is an anagram indicator.
'icon'+'is'+'man'='iconisman'
'iconisman' is an anagram of 'INSOMNIAC'.

'who' acts as a link.

Can you help me to learn more?

(Other definitions for insomniac that I've seen before include "Person finding it difficult to sleep" , "One lying awake" , "This person can't sleep" , "One who can't sleep" , "who won't get off?" .)

I've seen this clue in The Daily Express.

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