Doubt and unease in equal measure (5)

I believe the answer is:

qualm

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'doubt' is the definition.
(thesaurus)

'in equal measure' is the wordplay.
'in' indicates a hidden word.
'QUALM' is hidden within 'equal measure'.

'and unease' acts as a link.
I am not very happy about this link. Some or all of it may belong to another bit of the clue.

Can you help me to learn more?

(Other definitions for qualm that I've seen before include "Uneasy feeling" , "Feeling of doubt" , "Scruple" , "Apprehension" , "Anxiety" .)

I've seen this clue in The Times.

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