Pay attention: deli’s tenant missing some letters outside (6)

I believe the answer is:

listen

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'pay attention' is the definition.
(to listen to someone)

'deli's tenant missing some letters outside' is the wordplay.
'LISTEN' is hidden within the letters.
But, I am unsure how the hidden word is indicated.

Can you help me to learn more?

(Other definitions for listen that I've seen before include "Lend an ear (6)" , "16 (anag.)" , "Follow advice" , "Hark!" , "Attend (to a sound)" .)

I've seen this clue in The Times.

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