Discarded angora at the centre that had been delivered by boat? (5)
I believe the answer is:
cargo
'boat?' is the definition.
(thesaurus)
I can't explain the remainder of the clue.
Can you help me to learn more?
(Other definitions for cargo that I've seen before include "Shipment" , "Freight on board ship" , "Goods being transported" , "Goods in transit" , "Stuff on board" .)