Inexplicable message? (5)

I believe the answer is:

cable

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

'message?' is the definition.
(cable is a kind of message)

'inexplicable' is the wordplay.
'CABLE' is hidden in amongst the letters.
But, I am uncertain how the hidden word is indicated.

Can you help me to learn more?

(Other definitions for cable that I've seen before include "Thick wire; telegram" , "Anchor chain; type of TV" , "Strong line" , "Rope; message" , "A message transmitted" .)

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