Crossword Genius

Used to connect supporter with worker (6)


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'worker' is the definition.
(second is a kind of worker)

I don't understand the rest of the clue.

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(Other definitions for second that I've seen before include "additional > support", "Back-up; short time", "Time for a supporter", "A duellist's or boxer's assistant", "Unsurpassed".)

I've seen this clue in The Guardian.