Great tragedy to miss out on overtime — anyone there? (5)

I believe the answer is:

hello

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'anyone there?' is the definition.
(I've seen this in another clue)

I don't understand the rest of the clue.

(Other definitions for hello that I've seen before include "Greeting - celebrity magazine" , "Meeting greeting" , "A salutation" , "Conversation starter" , "Hi, howdy" .)

I've seen this clue in The Times.

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