Indifference of adolescent herds on the move (15)

I believe the answer is:

coldheartedness

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'indifference' is the definition.
The answer and definition can be both feelings as well as being singular nouns.
Perhaps they are linked in a way I don't understand?

'adolescent herds on the move' is the wordplay.
'on the move' indicates anagramming the letters.
'adolescent'+'herds'='adolescentherds'
'adolescentherds' anagrammed gives 'COLDHEARTEDNESS'.

'of' acts as a link.

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I've seen this clue in The Guardian.

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