Indiscreet record? (4)

I believe the answer is:

disc

I'm a little stuck... Click here to teach me more about this clue!

'record?' is the definition.
(eg a CD, compact disc)

'indiscreet' is the wordplay.
'DISC' is hidden within the letters.
But, I'm unsure how the hidden word is indicated.

Can you help me to learn more?

(Other definitions for disc that I've seen before include "Flat round plate" , "45, eg?" , "Record, CD" , "In Olympic event" , "Gramophone record" .)

I've seen this clue in the Evening Standard.

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