On a trip, top competitor (4,6)

I believe the answer is:

high jumper

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'competitor' is the definition.
Both the answer and definition are singular nouns.
Maybe you can see an association between them that I don't see?

'on a trip top' is the wordplay.
'on a trip' becomes 'high' (I've seen this before).
'top' becomes 'jumper' (I've seen this before).
'high'+'jumper'='HIGH JUMPER'

Can you help me to learn more?

(Another definition for high jumper that I've seen is " athlete".)

I've seen this clue in The Telegraph.

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