A famous Christian’s cycling broadcast (5)

I believe the answer is:

radio

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'broadcast' is the definition.
(radio broadcast is a kind of broadcast)

I don't understand the remainder of the clue.

(Other definitions for radio that I've seen before include "Broadcaster" , "MW, LW or FM sound source" , "Broadcast medium" , "Marconi invented it" , "Wireless broadcast" .)

I've seen this clue in The Guardian.

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