Medium may take daughter in for time to create relationship? (5)

I believe the answer is:

radio

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

'medium' is the definition.
(I know that radio is a type of broadcasting)

I cannot understand how the rest of the clue works.

Can you help me to learn more?

(Other definitions for radio that I've seen before include "Broadcaster" , "Receiving set" , "Transistor" , "Speech receiver" , "Part of the broadcasting industry" .)

I've seen this clue in The Guardian.

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