Get rid of flat-bottomed boat (4)
I believe the answer is:
junk
'boat' is the definition.
(type of Asian ship)
I cannot understand how the rest of the clue works.
Can you help me to learn more?
(Other definitions for junk that I've seen before include "Schlock" , "Transport" , "Chinese vessel - rubbish" , "ship" , "Sailing vessel; rubbish" .)