Fashionable indicator not used in brainwashing (14)

I believe the answer is:

indoctrination

'brainwashing' is the definition.
(thesaurus)

'fashionable indicator not used' is the wordplay.
'fashionable' becomes 'in' (in can mean fashionable or trendy).
'used' indicates anagramming the letters.
'indicator'+'not'='indicatornot'
'indicatornot' is an anagram of 'doctrination'.
'in'+'doctrination'='INDOCTRINATION'

'in' acts as a link.

I've seen this clue in The Daily Express.

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