Trip captain organised for one to join in? (11)

I believe the answer is:

participant

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'one to join in?' is the definition.
I can't judge whether this definition defines the answer.

'trip captain organised' is the wordplay.
'organised' indicates anagramming the letters.
'trip'+'captain'='tripcaptain'
'tripcaptain' with letters rearranged gives 'PARTICIPANT'.

'for' acts as a link.

Can you help me to learn more?

(Other definitions for participant that I've seen before include "player" , "Competitor" , "One getting involved in something" , "Actor" , "One actively involved" .)

I've seen this clue in The Times.

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