Extremely insensitive (4)

I believe the answer is:

dead

This clue is a double definition.

'extremely' is the first definition.
(as in a phrase like 'dead easy')

'insensitive' is the second definition.
(I've seen this before)

(Other definitions for dead that I've seen before include "No longer living" , "No longer alive" , "Defunct" , "Devoid of life" , "Passed on" .)

I've seen this clue in The Guardian.

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