Hauler sent up by scold? (11)

I believe the answer is:

semitrailer

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'scold?' is the definition.
Although both the answer and definition are singular nouns, I cannot understand how one could define the other.

'hauler sent up by' is the wordplay.
'hauler' becomes 'semi' (I've seen this in another clue).
'sent up' becomes 'trailer' (I can't justify this - if you can you should give a lot more credence to this answer).
'by' means one lot of letters go next to another.
'semi'+'trailer'='SEMITRAILER'

Can you help me to learn more?

I've seen this clue in the Sydney Morning Herald.

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