Transport subject to endless abuse (3)

I believe the answer is:

bus

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'transport subject' is the definition.
'bus' can be an answer for 'transport' (busing is a kind of transporting). I am not sure about the 'subject' bit.

'endless abuse' is the wordplay.
'endless' says to take the centre.
The central letters of 'abuse' are 'BUS'.

'to' is the link.

Can you help me to learn more?

(Other definitions for bus that I've seen before include "Charabanc" , "Use transport" , "Public service vehicle" , "Public transport vehicle" , "Road vehicle able to carry many passengers" .)

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

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